I was in the military and was driving considerable distances so opted for a 3. Highway 70mph cruising is 2,200 RPM. 75 in Jul 28, 2007 · S. Aug 24, 2015 · 1608 posts · Joined 2015. The gears you listed are transmission gears which would remain unaffected. Add stuff like the WS6/SS packages or convertibles and they get into GTO territory. 08 for an automatic car that is street driven. 55's would have been better stoplight to stoplight and 3. #10 · Dec 21, 2002. 00 Somewhere. Jan 28, 2013 · Everything is original except for the rear axle and differential. 78 or 2. Thats your gear. Dec 12, 2006 · Its the higher numerical gear ratio that reduces the overall torque rating. Probably a $100 or $200 repair by a pro. open? Aug 12, 2007 · Now, 1750 rpm. 46 / 1. A short gear with a 455 will limit its performance potential quite a bit without an up-side. We have a large selection of gear sets in stock and can recommend the correct Jul 22, 2011 · 3. It has leaf springs the rear is in a 1951 chevy truck that the person cut off all the mounting except the upper ears and welded leaf spring lowering kit and mounting bracket. The 05/06 differential will fit in the 04. 2004 Pontiac GTO. Motive Gear Performance Ring & Pinion Set, GM 7. The Julian date on that rear is the "149". That would be about the longest-legged I'd think of going with a 4 speed. 3 litre LS1. It's got about 20 passes on it with about 350 RWHP. 17-inch alloy. Based on a tire size of G77-18 (or equivalent 235/60/14 from the tire sticky section) that is a 804 rev/mile tire. Sep 12, 2013 · I know that '69 GTO takes a 10 bolt rear end, and is supposed to be either 3:90, or 4:33 geared. In the example to the left, 37 ÷ 12 = 3. Sep 7, 2022 · When I factory ordered my GTO back in 1967 the standard gear with the wide ratio Muncie was 3. To find the gear ratio, divide the big number by the little number. I even road raced it for over an hour when it was around 480 rwhp. 46. 56 rear end is super thin, and the pinion gear is huge. Not even sure what the original ratio was. Heavier car, needs more leverage to move it thus the change in gears. 93--3. The only way to get a stronger rear end is to get a 12 bolt or a Ford 9" or Moser. Wheels and Tires. Wheel size & type. 1964-1974 Tempest/Lemans/GTO Frame, Trans, Diff. 56 Dec 3, 2003 · The new 2004 Pontiac GTO is not an ear-shattering, liver-pummeling reincarnation of the original Goat. . No telling what gear the LeMans has unless you run the code or pull the cover to check the tooth count. Jul 12, 2009 · And What is the Rear End size for these Gto's? HELP! I am currently trying to research to upgrading my gear ratio from a 3. #2 · Jul 29, 2010. The problem is the rear end is a 2. 30 over with a COMP Cams Xtreme Energy Cam and Lifter Kits operating range 1,600-5,800 (COMP Cams CL51-223-4) and an Edelbrock Performer RPM Intake Manifolds operating range 1,500-6,500 (Edelbrock 7156). Apr 15, 2016 · I really think it is the way to go, with boosted car. Sep 12, 2019 · 66 GTO 389, 4 speed with 4. here are some images showing the differences between the BOP rear ends; This illustration is mainly good for noting the earliest Pontiac 8. 62, 10. Tomorrow I will start building a 455 bored . Typically the square hole in the plug is the same as a 3/8" drive breaker bar or ratchet. 55 Ratio - NEW | eBay. Oct 5, 2021 · Roger that. It is a 3. Some where over the past 49 years someone changed it to a 4 speed. Then tonight read that my housing might not be able to take a gear ratio above a 3. 73 rear gear…and these trans ratios are sweet I have 3. 91 3rd gear pulls hard in thru the 1/8 mile, almost perfect. Motive Gear Performance gear sets are made from first-run steel; never recycled metal. 36 gears in your stock 3. 2 in Feb 3, 2021 · If you are referencing the "P2. 78 or a 2. 08 or 3. Military And Law Enforcement Discount Sep 7, 2011 · 4081 posts · Joined 2005. 2:56 gears came in 6 cylinder Tempests and also in V8 Tempest/leMans/GTO's as an "economy"gear, and also was used in air conditioned cars: lower revs=less engine heat. I'm trying to ID what gear ratio I am working with. Look at all the rusted ones on eBay. 90 x 3. Do Anyone know the size for 2004-06 Rear End? Does anyone knows who sells gears for late Apr 6, 2024 · I found a 68 GTO complete 3:55 posi rear end, and needing to know if it will fit under a 1966 GTO/Tempest or a 1965 GTO my 66 Tempest is already pretty tight but would like to upgrade from the highway gear ratio in it or my 65 GTO coud use it as well as someone took out the original 3:55 posi and put something else in there. Oct 5, 2021 · I'm guessing you have a manual so the "highest" (lower numerically) I'd go is 3:23s which is also the highest ratio allowed by the factory in a 68 manual trans GTO. Perfect combo with a 400 or 455. Mar 5, 2024 · Based on documents, the car appears to be born with the M20, G78-14 tires, and a 3. 589 posts · Joined 2021. With the TH-400, 2. I would like to keep it a 3. 55 used the M-20 gearbox with the steeper first gear. 2 rears were introduced. Jun 1, 2004 · The Details. 36 ratio. 00 or 3. 08 is the standard ratio for a 403 in High Altitude Certification, but this is a very early buyers guide and may have been updated later. It is a 10 bolt posi rear, 56" flange to flange, and has parrallel ribs in the center section. 36 Ratio, GM, 8. If you had a small block Chevy 327, then the 3. 55:1, 3. Rotor diameter (in / mm) 11. 93 is an excellent gear for an automatic car, a bit long-legged for a 4 speed car. I am looking at different sites who sell the Jun 27, 2015 · 05GTO said: After a little more research I found the SD code was used from 1968 thru 1972 and the gear ration was 3. 36:1 on the order sheet. 08, but not as likely. 31. 55 has a meaty ring gear and a small pinion gear. Good all around performance. The 3. 5 inch. The only problem you are going to run into is the bolt pattern is different. The inside of the gears looked good and being its 2:56 gears it should do well on the highway. But on average, a GTO is about 300 lbs more. Specializing in 82-2002 Camaro and Firebird's, we offer everything from restoration parts, performance parts, used parts and services for all 82-2002 Camaro and Firebird's! Located in Easley, SC, we ship worldwide and also have a store front for local customers. Like. In town the 3. Non Safe-T-Track : WB -2. My car was originally 3. The 2004-2006 Pontiac GTO comes from the factory with a 3. 90. #3 · Sep 7, 2011. 23 - which my car came with originally (as well as a TH400). Again, sounds like you have the "correct" rear end for your car. 55 unit, except the ratio is all wrong for a stick car. Oct 6, 2011 · 2214 posts · Joined 2005. 450 at the wheels, and never tracked it. Turn the wheel 2 complete turns. Oct 13, 2013 · Sounds like a 3. Great hiway gear, if you have an automatic trans. I would stay with 3. Personally I see no problem driving with 3:55s on the freeway. 93 is a good ratio for Nov 27, 2005 · Location: Omaha, Nebr. I can't say that a "coppa" type order program was not available on the GTO. 55 unless I hear some convincing arguments to "upgrade". Oct 27, 2009 · So I am getting ready to install a rear disc kit on a rear differential that I thought was appropriate for my 1966 GTO. Both rear tires are not always spinning at the same speed. 55 and also get the correct speedometer gears for the tailshaft of your 4 speed. GM 7. 083333. No optional gears were available as original equipment. May 21, 2010 · Lots of information. 42 gear is definitely quieter than the 3. 7. Mar 11, 2009 · The correct rear end for your car will not have any c-clips for the axles. Yes, Pontiac TQ can pull these gears and it can get you some gas mileage Mar 23, 2006 · The new GTO coupe uses the LS1 340-hp V-8 and the high-ratio gears of the M12 six-speed to achieve the quickest acceleration possible for this drivetrain. 55 RING AND PINION - AUBURN POSI - GEAR PKG. This allows Motive Gear Performance ring and pinions to handle the extreme torque from high horsepower racing engines. One thing I noticed was that the GTO has a slower rear end and final drive ratio than many of the cars it's compared to in the car rags. Car wouldn't be pleasant to drive at low speeds below that number. 2" rear. But get the engine checked out! Aug 30, 2011 · Yes it will fit. Currently looking at an original 10 bolt Safe-t-track with a 3. Make sure that the car is quite stable, get under the car, and TURN THE DRIVESHAFT. Mar 19, 2023 · 1969GPSJ. One thing you don't want is to have your stall speed higher or the same as your cruise speed. When I did the rotisserie frame-off restoration of my 66, I purchased a 3-turn box. The '67 is an automatic and netted me over 19mpg on a 550 mile trip last weekend. 3. 90's and the 3. For your 428 with a TH400 and for your purpose, I'd go with a 3. If it takes about 2 and three-quarters turns, it's around a 2. 2 10 bolt, possibly an early '66 8. I have a 1964 Tempest Le Mans 2 door Pillar Post Coupe and I'm having trouble determining the stock rear axle ratio. The tallest gear Pontiac put in their 4 speed GTO's was the 3. just recently put in a built rear end with 3. #10 · Jul 13, 2007. Start by lifting the rear end of the car off the ground. The best way of doing it would be to buy a one piece drive shaft. Speed confirmed by GPS. 93 rear gear. 36 and up gears. Seriously wrong. 55 gear. 4 = 11. SensitiveRob Discussion starter. In some of the high horsepower models, there were some Chevy 12 bolts used, but they are few and far between. 2"- BOP - OLDS PONTIAC- 3. Some guys install what's called a 'ring gear spacer' behind the ring gear on a carrier assembly to convert it over to lower gears. It used the Chevelle 12-bolt center section with shortened fullsize axle tubes and brakes. 56 & 2. 08's. Calculate the Ring and pinion Teeth. Jul 28, 2005 · Yea, on an auto car a torque converter is the biggy. 33. This one is the stock 3. Aug 31, 2009 · A-body and b-body rear ends were not interchangeable, more than likely the rear end is from a chevelle. 55:1. 42 pinon has 12 teeth on a 41 tooth ring gear whereas the 3. the 5/6 gears on the highway are noticeably different than stock GTO ratios. 4-wheel discs (ventilated front, solid rear), power assisted with 4-channel anti-lock braking system. The average F-Body weighs 3,400 - 3,500 pounds. Jan 30, 2014 · Aluminum drums are available as a front end option only, and metallic linings are available with all axle ratios except 3. Jul 12, 2012 · I opened up the rear end of my Tempest with the expectation of a quick look and refill with gear oil and found metal chunks in the bottom. 73s for 20 years and I had tons-o-fun. 91 or 3. Dec 26, 2011 · Bear, I plan on over half of my driving on the highway. According to the markings/ID on the axle tube, the gearing is supposed to be 3. 73 gear ratio. General Motors rear end differentials are referred to by the diameter of the ring gear, i. Jan 13, 2017 · 190 posts · Joined 2014. The axle gear code for Pontiac should be Feb 27, 2011 · That said, my heavy, low compression, TH400 '67 GTO convertible has a 2. 70 = 7. Sep 24, 2018 · The easiest way for a gear swap (and the cheapest) is to pick up a complete used rear end and bolt it in. Jul 31, 2013 · If I went with zr1 ratios, I think it would be too tall despite all the torque. Originally was a Safe-t-track but was replaced with a standard rear end after he cracked the casting. 93 and stock torque converter. This does not take into account the added mass you added to the car as far as weight. 55 posts · Joined 2007. One way you may be able to find out, if the rear has been swapped but the trans is still in the car is by checking the speedometer drive and driven gears. #4 · Nov 27, 2022. Aug 27, 2012 · 12420 posts · Joined 2008. The casting number 9779822 is going to be from a '65 Pontiac 8. 55 ratio gears were reproduced for this style rear aprox 10 years ago. If you can’t find a stamping or it is unreadable. I have a '71 rearend. Very clean housing and cover as you can see. Pontiac GTO 2004 Drivetrain & Rearend. 2 rear end made. 70:1 Ratio, 7. Find 2006 PONTIAC GTO Differential & Rear-End Components and get Free Shipping on Orders Over $109 at Summit Racing! Gear, Ring and Pinion, 3. 2004-2006 GTO General Discussion Other than potentially different gear ratios are there any differences in the rear ends? One stronger than the Find 1967 PONTIAC GTO Differential & Rear-End Components and get Free Shipping on Orders Over $109 at Summit Racing! Ring & Pinion Gear, 3. If you have a casting date part of May 1966 it could not been a 65 model year part. side note:make sure you can get the fill plug loose before draining the rear, you should be able to locate the stamping on the ring gear (see pic) divide the larger # into the smaller number to decipher correct rear ratio, the pic shown is a 3:55 ratio. The book I use for rear axle casting numbers for the 65 model year is called the 1965 Tempest Inspector’s guide. Looking for the best solution, not necessarily the cheapest. It also says that 3. Then you can always count all the teeth on the pinion & ring gears. Gears are 3. 04-06 GTO GM 3. 33:1 was offered in the 12 bolt which was standard with the 455 engine. 08 up through 3. 4 x Aspect Ratio x 2 + Wheel Diameter = Tire Diameter in Inches (Height) EXAMPLE (285x70R15): 285 / 25. same clutches were used in the 12 bolt original Chevy car & truck eaton posi carriers. Nobody I know of makes the 3. It held a non-posi with 3. Pontiac axles are held in at the flange. 5 inch, 10. Aug 12, 2013 · HD is 4 pinion as compared to 2 pinion on a stadard rear end. Feb 19, 2009 · Check the date code which is located to the right of the cover, top right on the housing. #1 · Mar 19, 2023. You need to know what carrier you have, as well, as it will determine what gear you can replace your present gear with. Rear gear change 3. It makes the car feel a lot lighter and more nimble. I own a 69 GTO with an open diff. That does mean 3. 56 was common in Tempests for economy. After a little more investigation, I am not sure what the year and gear ratio is. 25 posi expecting super-fun and I can barely burn out because my trans is so tired (from all that old fun). GTODEALER. The GTO uses the higher ratio fifth gear from the M12 used in the 2004 Corvette Z06 to maximize acceleration. The rear axle is the stock 10 bolt 8. 2004 GTO 2004 Mach 1 Paint Jun 27, 2005 · No gear noise or other noises, the new diff cover is the shiznit, there is less rear end body roll and plants the rear much firmer. 73 would be the gear of choice. Time to verify your rpm and road speed. 12447 posts · Joined 2008. That is probably the strongest 8. G. 23 posi and they only had to replace bearings and seals the posi unit, carrier and ring and pinion were fine. Apr 23, 2005 · It seems that the GTO's power to weight ratio is better than some other cars that end up doing better in the car rags (Mustang, STS-V, 300C SRT8). and I am having a touch time with the research. 3000 RPM at freeway speeds is nothing to worry about. With heads and cam it's almost too much in first gear tho. Like was said, the Ford 9" would be the best way to go. The Pontiac GTO's engine is a naturally aspirated petrol, 6 litre, overhead valve 90 degree V 8 cylinder with 2 valves per cylinder. The gear ratio list provided does not include all optional gear ratios. Performance-wise, 3. It drives much more like a modern car and it was a good choice. Apr 11, 2024 · For racing, the 2. Be sure to call or email us for any of 2004 Pontiac GTO. If it was an AC car, probably a 2. In the 04, the bolt pattern from the drive shaft to the rear end is narrower. Pontiacs came with 3. Performance & Service. Feb 1, 2007 · no, your car has 3. Sep 23, 2021 · my car was a one-legger with 2. Codes are described below with their location. Jan 31, 2015 · If you want to be bulletproof, and do it once, the 9" is the way to go. They have boxes that are 3 turn lock to lock and also 2. Apr 22, 2023 · And the common 3. 23 but sadly not much on this car is original. I took it to a shop and they rebuilt it for around $500. I Am Not Sure What Stock Gear Is I Think Its In Low 3. Nov 27, 2022 · 12361 posts · Joined 2008. Jun 13, 2017 · Lower ratio 31 spline posi carriers, as well as nice used condition 3. 10. Or 3. Feb 21, 2015 · You decreased your gear ratio by 9. 2004 Blk/Rd M6. I read on another website that you can manually check it using this method: Determining Gear Ratio You will have to put the rear up on jackstands, put the transmission in neutral. Something is wrong with your tune or combo. 73to ? Jump to Latest Follow Jan 1, 2012 · A '68 Pontiac would have had an 8. #6 · Oct 6, 2011. The base model Z28's and 1LE's can tip as low as 3,200. Apr 26, 2019 · Yes, any 80W-90 gear oil will work. I have 3. #4 · Mar 19, 2023. 23 but can't find a carrier. There is a thread in this section about how to tell the difference between an 8. 75" 9-bolt Rear End, 3. 55:1 and 3. 8540 x Sep 4, 2023 · If your M21 is original to the car, your rear end is a 3. 36's are a straight bolt in. Guage how many turns the tire has done. #10 · Aug 26, 2015. 31:1, 3. 2" and an 8. 6% or say 10% You would need to increase your gear ratio to 3. Ames says that standard box is 4 turns lock to lock. 55. Jan 12, 2024 · The proper rear-end gear ratio can be selected using the following simple formulas whether using a direct-drive (1to1) or overdrive (usually 30%) transmission. 2" BOP 10-Bolt Rearend Posi Gears Bearing Kit Package - 3. Give us a call at 800-216-1632 to get started. Nov 23, 2017 · For a Posi rear end: Jack both wheels off the ground. #1 · Nov 26, 2014. No difference in appearance or measurements. I have a 65 GTO with the standard 3. 23 gears, you'll need to get a carrier that spans from 2. Transmission needs to be in neutral. 56 limited slip and it FRIES the tires. - Count the turns on the drive shaft. If this helps, the car came stock with a 326 V8 and 2 speed automatic transmission. agree with LATECH, maybe upgrade your 2 speed for more fun first? or are you asking about gear ratio over posi vs. 90:1 and the 4. Considering changing the rear end verses going to a Gear Vendor. See the rear end gear sticky for more info on gears and carriers. Altering gears changes the rate of acceleration, high numerical final gears will give faster acceleration, but hurt the top end pulling power, where as the reverse is also true. armyadarkness and PontiacJim. Mid-Engine Corvette’s Rear End Possibly Jul 28, 2010 · geeteeohguy. 08 and higher numerical gear ratios for the 4 speed cars. I agree with Army, though----if it is the original rear end, have it repaired. I would not use a synthetic. 91s) while cruising around town. Apr 2, 2009 · OK. 23's would have been nice for the open road. The front of the 98-02 T56's is different though, with a slightly longer input shaft, and the slave cylinder for the hydraulic clutch moved from the side of the bell housing to the front of the tranny cover, concentric with the input shaft. e. 33's & the 4 pinion low ratio carrier in separate deals. The first '66's were the same width as the the narrow '64-65 Pontiac 8. It doesn't do it from every stop, maybe 1 in 4 times when you take off Nov 26, 2014 · 3 posts · Joined 2014. #2 · Jun 26, 2021. Apr 23, 2014 · Wally, the easiest way to check your gear ratio is by counting the revolutions of the drive shaft on one complete turn of a rear wheel. Nov 29, 2021 · 49 posts · Joined 2021. Multiply by two. 56 is the "correct" unit, as it looks and is constructed exactly like the 3. 2 BOP gears are available from Summit, Jegs, most all the online rear end shops, Ebay sellers, and many other places. I know there was about seven options. Apr 6, 2020 · The 2004-2006 GTO. 00 ratio is not expensive, as long as it's not a tru-trak (posi). #2 · Jan 13, 2017. 55:1 rear gear ratio quickens the wide powerband of the DOHC motor far better than the earlier Cobra's 3. Includes the rear mounting bracket that attaches to the rear cover along with both wheel speed sensors. armyadarkness, GrandTO and Goat noob. There are 3 carriers: 2 series, 3 series, and 4 series. 07, the closer ratio of the fbody trans should keep acceleration constant and help with traction in the heavier gto. For a Non-Posi rear end: Jack one wheel off the ground. 5". FIGURING TIRE DIAMETER (Height) FORMULA: Tire Size / 25. 90 Gear Ratio $ 581. Sep 28, 2011 · The '71 rear end will bolt right into the '66. Turn the rear wheel Mar 19, 2023 · Goat noob Discussion starter. Limited slip means it is not a full true locked Posi rear end. 27 ratio. 73 pinion has 11 teeth on a 41 tooth ring gear (gear pitches are different). All you need to do is change out the driven speedometer gear in the trans and you are good to go. or sometimes double clunks. 2 rears. It is too early to tell about gas mileage. Posts: 543. Engine: GM LS1 all-aluminum, pushrod V-8, bore and stroke of 3. 2" BOP - BUICK OLDS PONTIAC - 3. Both goats gone. My 1967 GTO was born an automatic. I just jacked up my rear end and rotated my tire 1 full rotation ans my driveshaft made 1 3/4 revolutions. Save Share Dec 20, 2002 · 14180 posts · Joined 1999. 2 Pontiac rear. The zr1 is a couple of hundred pounds lighter than the gto and has a 3. 46 Gear Ratio Rear Differential USED Picture for reference only. Could be a 3. Sep 7, 2006 · First find out if you have a posi rear or straight axle by rotating one tire, if both tires turn in the same direction: posi, different straight. 42 final drive. = 72 mph. I want to convert it to limited slip but all I can find carrier wise is 3. 07:1, 3. 31 gears. My rear is stamped for a 3. 11 would put your revs up much higher. Nov 12, 2016 · Ring and Pinion Gear for GTO. These are 3. #4 · Oct 6, 2021. I am thinking a 3. 5 turns. For a car that sees about 75% of the time on the street or more, leave the 2. 3. 08 ratio. A 3. 5 inch, 8. The Pontiac GTO is a rear wheel drive vehicle, with the motor located in the front, and a 2 door coupé bodyshell. 23 or go to 3. 99. 90:1 in the 10 bolt, the 3. 2nd gear is much nicer to live with, that was the main reason I did it. 11 rear end ratio. The 1979 Pontiac Buyers Guide lists the 2. 2 open rear end. Axle/final-drive ratio:1. It's got about 30 passes on it with 480-505 RWHP. If you want actual 3. Lets assume Pontiac knew what they were doing and its close to a good all around set up. Better off with a 3. 56--2. What I did when I changed mine on the '65 back in 1990 was find a good used set and I went that route. 93-3. A little later in '66 production, the slightly wider Pontiac 8. But I seem to have pretty bad luck with stuff breaking. 23's are a much better gear for a 455 than 3. The 2. My rear end went out (along with my truetrac and 3. Here is a picture of a type-c chevy 12 bolt diff cover that was used on chevelles and was an option for the 70 GTO 455HO. So, to compensate for the taller 3. 55 RING AND PINION - EATON POSI - MOTIVE GEAR PKG. 55 rear end, I will verify after I install the engine. 23 ratios. Turn one wheel 1 complete turn. the rear end of the car no longer feels mushy when accelerating and turning, cant wait to change out the swaybars the hotchkis or slp. 7 / 11. 41 posi axle as the standard axle ratio on 403 T/A's, but it lists 3. 93. If your '66 is an automatic, a 2. 46 rear gears as is. If it is a '68, there should be a 2 letter axle code stamped on the back drivers side of the axle tube. It get's a lot of hard 6-3 downshifts and a lot of 0-70 blasts on the street. In my experience, having driven these cars with every ratio rear end, the best all-around gear ratio for your car would be a 3. 2, there are posi units & gears in different price ranges. 93 units are not sought after (yet) and are generally in mint condition due to their life as a cruiser rear end. Not too bad for mileage. It should read like, d158. Looking at your sheet, your car definately came with a close ratio M21 and a special order rear gear. 22 x . 70 Gear Ratio is perfect for dedicated racing or off-road vehicles. 23 rear end gear. Jan 1, 2018 · Here is what I know: 1. In '67, the standard ratio with a 4 speed was 3. The tallest gear Pontiac provided with a stiskshift GTO was a 3. 73's are not surprising. 93 which is what came on automatics with a/c. Apr 12, 2004 · Power output is impressive and the addition of a 3. One of the higher priced brands that have had a good rep for many years is the Richmond 2004-2006 Pontiac GTO Rear Spoiler NEW GM NOS Part 92161980 Item shipped as shown. These linings are standard equipment on all production line vehicles Jan 28, 2015 · The 1964-1974 Pontiac Tempest, Lemans & GTO. 08 gears. Car: '04 Pontiac GTO, front engine, rear-wheel drive. Jun 26, 2021 · 7834 posts · Joined 2012. Both Moser and Curry, and probably others Feb 2, 2008 · A 2. 97. Thoughts and recommendations appreciated. For straight axle rotate the rear wheel until you get one full turn of the driveshaft. 91s on the goat. 25 rear gear ratio. 93" it is the way they stamped the rear gear ratio on the '64's from what I found on the internet, so it is supposed to be a 2. Dec 6, 2018 · Nice, low mileage (~12K) Pontiac 2006 GTO rear end differential. #3 · Sep 19, 2018 (Edited) Yeah, 8. "8" being '68. When I take off out of the driveway and go from Reverse to Drive and gently accelerate, I get a popping or clunking sound coming from the rear. 55 rear end, and save your original gears. 2 10 bolts and earliest Buick cast (single rib) 8. The Z16 rear was a Chevelle/full size rear end hybred. Before pulling off the rear differential cover, I would first make sure that you can remove the fill plug. 50's and up will limit your highway cruising ability and cost fuel mileage. So far I'm happy with driveability and the highway RPMs of my current setup. It is like "Clunk". 23 for a stick car, and a 2. 6. 73's. That's not a super stressed area, as you can tell by the flimsy factory locating arms. 2 10 bolts. 36 is as long legged a gear as you can go with your 4 series carrier, so you can remove the 3. Good luck!! Jun 12, 2007 · Rear End Gear Ratios Lemans & GTO General Discussion 2004-2006 GTO General Discussion 1964-1974 Tempest/LeMans/GTO Tech/Electric Wiring Service, Apr 28, 2013 · This is because the ring gear on a 2. 08:1. All the other 4 speed ratios from 3. 08:1, 3. GM 8. 93 is not ideal. 70 from 3. 46 gear ratio limited-slip differential. Sell off the 4. If I were you, I would run the piss out of it and if you happen to break it, then go to a stronger type. Sounds like your '67 either had a 4 speed swap or a rear end swap. This powerplant has an output of 400 bhp (406 PS/298 kW) of power at 5200 rpm, and maximum torque Jun 17, 2021 · Hawks 8. Sep 8, 2021 · 7 posts · Joined 2021. 73:1 Ratio, GM, 12-Bolt Sep 15, 2009 · (the entire rear axle assembly). #1 · Nov 29, 2021. 90 or 4. 23:1, 3. 46 I Did Purchase An A4 Because Of City Driving. Jul 10, 2017 · Yeah, if you wanna stay with your BOP 8. Steering box. 474 posts · Joined 2020. Nov 27, 2017 · In that case, if not concerned about the limitations of less pinion support & of crappy sealed axle bearing axles, you could have the nodular 8. 46 to an 4. What came on 4 speeds with a/c was a 3. The AMA specs for the Tempest include gear ratios 2. And, like most other parts, there are different brands, with varying prices. The last production date for the 65 model year was August 19, 1965. Thanks Find PONTIAC GTO Differential & Rear-End Components and get Free Shipping on Orders Over $109 at Summit Racing! Ring and Pinion Gears, 3. Gforce's 9" rear end is only $3600, unless you option it out as expensive as possible. 8 Rear End. Mar 25, 2005 · I Am Currently At 470 Hp At The Crank Do The Math For The Rear Wheel, My Problem Is I Want To Purchase A Rear End Gear That Will Really Show The Hp Without Spinning The Tires Out Of Control. 23 ring and pinion. 23 as an available ratio with the 403. 2 built with a mid ratio Auburn posi carrier & a good used set of 3. A 2 series gear with a 4 speed isn't the greatest, so yeah, you should re-gear. Again, if I had your choices, I would put the 3. #1 · Jul 28, 2007. Many have had that done. My favorites are a 3. Would like to turn this into a better touring car. 08. Here's a list of codes and ratio's. 438 posts · Joined 2010. 1:1 compression ratio, 92-octane fuel, 350 hp at Jul 13, 2007 · 11127 posts · Joined 2005. 73 because of the increased gear contact area. 23 peg leg rear end. #13 · Sep 9, 2021. Nov 7, 2011 · 1964-1974 Tempest/Lemans/GTO Frame, Trans, Diff. #6 · Aug 28, 2012. Type. 23 8 7/8 P series (Pontiac) gears are very very hard to find. In 72 Pontiac offered the GTO with the 3. 46 gear ratio. Much better. Nov 21, 2008 · That being said, until '70, all GTO's had the ten bolt rear end. Accessories. I called SummitRacing and many others to try to switch out from a 3. Lucas brand is a good choice and what I have used. The best way to know what the gear ratio is is to find the axle code on the axle tube, or use the factory documents purchased from PHS that will list what axle the car was born with. Our experts will help you find the correct ring and pinion set for your particular application. Put a piece of masking tape on the drive shaft and a piece of tape on one of the rear wheels. Sep 19, 2018 · 804 posts · Joined 2016. So I would like to change mine to the 3. My code is upside down. 42 & 3. 2. 23. Good in town, good on the freeway. if ud bp aa bn qh ut fd ge gh