I recently purchased a 1970 Buick LeSabre Custom Convertible with a Buick 350 and a TH400. This is my first Buick and I don't know much about Buick rear ends. Looking at my differential cover, it has 2 notches (left and right side of the cover) and based on the 1970 Buick Chassis manual, it looks like I have 43-44-45000 differential. The manual also shows a 46-47-48000 rear end with a more square cover (no notches). What is the difference between the two types of rear ends? Is the one I have for small block cars and the other for big blocks? I have a 75 Buick 455 that I want to build (likely nothing wild) and swap in place of the 350 - will the rear end I have be able to handle it? Any info about this rear end would be helpful.
Standard rear was a 2.93 1968-70 Buick 8.2" . There are no repro gears for this rear. Used gears are out there but hard to find for the higher numbers. The rear will take some but not a ton of abuse. The GS455 has the same rear in 1970. The 4600 4800 and 4900 series rear that year was a 66-70 Buick 9 3/8". It is tough and almost bullet proof but again no reproduction gearsets are made.
Thank for the info. I have not had a chance to find the stamp on the left axle tube yet, but suspect I have the standard 2.93 ratio non-posi. I don't plan on too much abuse - that's the plan at least so hopefully I will be ok. I will keep my eyes open for a posi carrier with better gears or for the stronger rear, but it sounds like that could take years. Was the stronger rear used in full size big block cars? Is it a bolt in swap between full size Buicks? From which years? I also seem to remember reading that all Canadian models came with posi? Is that true?
The 9 3/8 will not fit your housing. You might see if a 9 3/8 will fit drum to drum. I think it will because I think a 70 leSabre 455 was a 9 3/8. Also the Estate Wagon and the Wildcat used the LeSabre platform in 70 so they are likely donors. Yes the 9 3/8 in 70 came in the Lesabre 455, Wildcat, Estate Wagon, Electra, Electra Custom and the Riviera. The Canadian rear was a different deal just for Canadian made cars.
just to clarify things, 64-67 8.2 rears from a buick is the chevy c-clip style(weaker but can easily find aftermarket gears and posi?) and the 68-70 8.2 is buicks version(bolt in, stronger, but no aftermarket support?)
I'm not positive about the year ranges, but my 65 8.2 has got bolt in axels, its the BOP 8.2 rear. The later ones are the Buick 8.2 and have no support and c clip. Experts correct me if I'm mistaken. Thanks
This is not correct 64-67 Buick 8.2 rears have nothing in common with chevy 8.2 rears. they have bolt in axles. They also have stronger pinion gears with more splines. the 64-67 Buick 8.2 shares gears and carriers with 64-71 Pontiac 8.2 rear ends and also 64-67 oldsmobile 8.2 rear ends. Aftermarket gears are available in 3.55.3.73 and 4.11 through richmond. Posi carriers are available through Auburn and eaton
Geez Will anybody get this correct....lol 64-67 pontiac 65-67 buick 65-67 olds f85 65-66 olds all use the same carriers and gear sets and used right handed thread 3/8 ring gear bolts (SAME AS THE AFTERMARKET GEARS AND POSI UNITS SOLD TODAY) 1968 is when the S**T hits the fan for the BOP world of axles...lol. ou: 1967 olds came out with a 12 bolt olds rear for the 442 cutlas 28 and 31 spline option axles. 1968 Buick switched the pinion gear sHAFT (AND REALLY THE WHOLE DESIGN OF THE PINION HEAD) to 1.875 (no aftermarket support for gears just posi carriers and even then the units were 7/16 holes for the 7/16 ring gear left hand thread bolts. 1968 -1972 THE TEMPEST REARS (pontiac) uses the 7/16 left handed thread bolts also...so the posi unit will not fit the early rears gear sets or the aftermarket gear sets. 1971 1972 olds and Buick rears were 8.5 10 bolts totally different axle spline at 45 degree angle 28 spline. all othert 10 bolt 8.2 rears use the 60 degree axle spline angle 28 spline. ALL 1965-1972 BOP rears are BOLT IN AXLES. If they are c-clip it is considered a CHEVY axle. up to 1972. after that it was considered a corperate alxe 10 bolt 8.5 for the first few years the Buicks olds and pontiacs still had bolt in axles then everything went to c-clip at about 1976ish area and by 1978 everyone had c-clip rears and we were down to the 7.5 rears...OH NO....o No: axle seals are another issue 1964-1968ish used inner axle seals then in 1968 1969 most 10 bolt and 12 bolt olds rear and the 1971 1972 8.5 rears all used the internally lubed bearings and external axle seals that are found on the axle outside of the bearing and infront of the alxe retaining plate. WOW hope this helps everyone....And of course i am sure someone will find something else wrong....BUT these are pretty darn close to fact as I have learned all this info tearing down and rebuilding rears. I have seen all this. I am sure there is more to learn and am doing that eveyday. Stay tuned...lol. Take care guys. Jim J D Race.com I just wish I had time to get it all on my site.
Well this never got finished huh? Seems to me as I reread this whole post the first gentleman was asking about a 1970 lesabre. How we got on skylark is beyond me. The 1968-1970 Lesabre should have the same center cast center section as the 1968-1970 Buick skylark though. This i have done research on in the past year so this is a relevant post. So you can use the skylark 68-70 gears AND posi unit in a 1968-1970 Lesabre. We do now have aftermarket gears for both 3.42 and 3.64 which fit the Auburn aftermarket carrier with small mods and one passenger carrier conversion bearing. I hope the 68-70 Lesabre guys are reading and for the street as long as the set-up is done to GM specs it will hold for street big block application. Jim The square cover rear is a much larger Buick 9 3/8 as stated and NO aftermarket support at all.
jim I also have the 70 lesabre w/455 my rear end appears to be canadian pontiac 10 bolt cov.w/12 bolt ring 9 3/8-9 1/2 Iam tring to replace the wheelbearings on this unit non clip style can not find them anywhere.Do you have info on this setup thanx tumblersearcher
10 bolt cover with 12 bolt ring gear is a 8.875 IF it is a FULL SIZE pontiac rear. not 9 3/8 that is the Buick rear and olds full size 12 bolt cover rear ring gear diameters. RW508BR bearing sealed 8940s axle seal pontiac uses these bearings 8940s seal 88131R bearing You really need to pull the beast to get it right. The old one should have the number stamped or etched in the bearing OR at least we can id it with measurement to be sure we have the right one. I wish it was just that easy to know BUT so many years and people swapping rears in and out of cars. JUST never can tell with out pictures and numbers. Jim
I have pulled both axles at this point the number that I have come up with correspondes with the 88131r number .These bearings do not sem to exsist anywhere .The local bearing guru is going to build a pair for me at less cost than the reg. lesabre bearing (508br)#which is available everywhere. The reg. buick 12 bolt bearing is smaller in o.d.also the thickness which sets the end play is to narrow thanx for the seal #.the seals seem to be a fairly standard size and available. When measuring the ring gear is the correct dia. taken from the o.d. or is it the i.d. thanx for your help.Does anyone Know were the 88131 bearing might be available or possible cross over #
I noticed you were on line. You have an extreme amount of knowledge. I have a 1969 Buick GS 400 4 sp. I have what appears to be an 8.2 rear. Doyou know what would be a direct swap drum to drum rear end wouild swap right in. Year make? I am confused with all of the choices and am looking for a simple solution Thanx if you can help me. mk50@msn.com 64-67 pontiac 65-67 buick 65-67 olds f85 65-66 olds all use the same carriers and gear sets and used right handed thread 3/8 ring gear bolts (SAME AS THE AFTERMARKET GEARS AND POSI UNITS SOLD TODAY) 1968 is when the S**T hits the fan for the BOP world of axles...lol. ou: 1967 olds came out with a 12 bolt olds rear for the 442 cutlas 28 and 31 spline option axles. 1968 Buick switched the pinion gear sHAFT (AND REALLY THE WHOLE DESIGN OF THE PINION HEAD) to 1.875 (no aftermarket support for gears just posi carriers and even then the units were 7/16 holes for the 7/16 ring gear left hand thread bolts. 1968 -1972 THE TEMPEST REARS (pontiac) uses the 7/16 left handed thread bolts also...so the posi unit will not fit the early rears gear sets or the aftermarket gear sets. 1971 1972 olds and Buick rears were 8.5 10 bolts totally different axle spline at 45 degree angle 28 spline. all othert 10 bolt 8.2 rears use the 60 degree axle spline angle 28 spline. ALL 1965-1972 BOP rears are BOLT IN AXLES. If they are c-clip it is considered a CHEVY axle. up to 1972. after that it was considered a corperate alxe 10 bolt 8.5 for the first few years the Buicks olds and pontiacs still had bolt in axles then everything went to c-clip at about 1976ish area and by 1978 everyone had c-clip rears and we were down to the 7.5 rears...OH NO....o No: axle seals are another issue 1964-1968ish used inner axle seals then in 1968 1969 most 10 bolt and 12 bolt olds rear and the 1971 1972 8.5 rears all used the internally lubed bearings and external axle seals that are found on the axle outside of the bearing and infront of the alxe retaining plate. WOW hope this helps everyone....And of course i am sure someone will find something else wrong....BUT these are pretty darn close to fact as I have learned all this info tearing down and rebuilding rears. I have seen all this. I am sure there is more to learn and am doing that eveyday. Stay tuned...lol. Take care guys. Jim J D Race.com I just wish I had time to get it all on my site. [/quote]
[/QUOTE] A 68-70 Buick A body is your donor. If you want the same gearing it will take another non AC car which will likely have a 3.64 rear ratio. If it is an AC car you will need a 68-70 Buick with a 3.42 which is most likely to be found in an AC car.
We have aftermarket 3.42 and 3.64 gear ratios now. 68-70 Buick Skylark and Lesabre 10 bolt 8.2 rears. We also have posi units that fit the stock 2.56 2.73 2.93 We have posi units that fit the 3.23 3.42 original gear set too. We can do some machine work to aftermarket carrier bearing hub to get a POSI unit to fit the original 3.64 and steeper gears too. SO- we have plenty of parts out there we can hook you up with Some paets like the 3.42 and 3.64 gears are kind of expensive and in small quanties...BUT they are available. Please PM if you need help sifting through the info. Jim
