I have a 71 GS 350 with a 1 legger 8.5 rear.I just picked up a 8.2 3:08 or 3:23 posi from a 68 or 69 olds.Drained the oil,everything looks good.The guy I got it from thought it was 8.5,but after looking at it and knowing what to look from George's site I knew it was an 8.2.Is this a good idea to switch to an 8.2?Will I need to change anything?Driveshaft length?Any help or advice is much appreciated.Thanks,Tom.
i did the same thing , but reverse. went from 8.2 to 8.5 everything bolted in the same. reason for swap was 8.2 was a one wheel 2.42 and i had gears and a posi out of a 8.5 trans am 77. 3.42. so i got mine out of a 76 malibu,ans switched guts, reshimed and tested, and installed. the brakes on the 8.2 will be smaller, as the drums, but everything fit fine, suspension wise. good luck!!!:3gears: :3gears:
Driveshafts are different from the 8.2 to 8.5. I think there is an inch or two difference. I have to swap my driveshaft in my 70 car since I am installing an 8.5 instead. If you plan to rip on it,be advised they aren't nearly as strong as an 8.5.But,with those gears,you should be ok.
I believe that is right. I have the driveshaft from my 8.2 thats about 55-57 inches and I also have an 8.5 I can measure them tomorrow and get the lengths for you. It shouldn't be terribly hard to get the right shaft for your car.Someone on the Island surely has one.
Thanks big,I'm thinking if it would be easier and cheaper to change my 8.5 1 legger into a 3 series posi,then going this route.
Factory 8.5 driveshafts are 7/8-1 1/8" shorter than same bodystyle/engine trans equipped vehicle with any 8.2 10 bolt, type "O", or 12 bolt. With all the positive attributes of the 8.5 A-body rear, personally can't see going with any sealed bearing axle 8.2 rear. BTW, the rear in above pic appears to be a '68-70 Buick 8.2 rear. What is the casting number on the center housing? Got Posi? :3gears: Roger
Thanks Roger,I got the rear for $300. and know where to find the driveshaft for it.So it's probably going to be something I can do myself,where if I try and change my existing non posi 8.5 to posi it would run quite a bit more money including the labor for someone else to do it.I can always keep the 8.5 for the future.Besides it's not like I'm racing,I think the 8.2 posi will be fine for my needs.At least that's what I've been told.
At the least, it's smart to pull the axles, remove the sealed bearings, examine the axles, & if the axles are not chewed, replace the sealed axle bearings. Too many are chewed under the bearing & ready to let go. When they let go, sheetmetal damage usually results... thus adding a lot more expense than that of say... adding a good used posi & new gears to an 8.5 A-body rear. Got Posi? :3gears: Roger
I believe 68-69 Cutlass came stock with 12 bolt rear end, posi or not. I owned a 69 cutlass and it had a 12 bolt rear end. George
The olds Type "O" 8.2in rear end had a housing cover that has 12 bolts I believe... I can't remember what mine had. To the OP. I ran a Olds 8.2 with a 4:10 posi behind my mild 455 for a couple of years of abuse with no problems. Sold it so another member, don't know if he's got it on the road or not yet. I liked it, but would definatley take OPH's advise and check it out... Don't want one of those comming off:shock:
What do you mean exactly,by letting go and sheet metal damage? Also where do I look for the numbers you asked for? Here's another shot.
From the axles comming out of the housing with the tire attached while driving... OUCH!!! kiss your quarter panel good by.
NO.. just more prominent with them. OPH knows better than I (I think he advised me when I got mine..lol). Something about the bearing being sealed or not getting enough lube, and chewing the axles up so they slip past the bearing easier.. I don't remember for sure. Held together for me nice though, but I'd definatley check it out before you run it.
The sealed axle bearing design is internally lubricated. Eventually the sealed axle bearing will seize & when it does the inner race portion of the bearing will rotate & chew into the axle where the bearing was pressed on. When this happens, the press fit of the inner race to the axle is no more... only the inner bearing retainer remains to hold the bearing on the axle. With time, & slow speed cornering, side forces will pull on the axle enough to pull the tapered axle through the steel retainer, & out the axle will go. On many other occasions I've run across worn sealed bearing axles that instead of pulling through, literally broke in the heavily chewed area. Either way, the result is nearly always the same, the tire & wheel exit the vehicle, damaging the outer wheel house & 1/4 panel. For 1970 model year, GM went to tapered wheel bearings in all bolt-in axle applications. The tapered bearing design wheel bearing receives splash lubrication. Ford eventually did so as well. Wider tires were becoming the norm & sideloading forces were increased. This move by GM & Ford Engineering was not coincidental, both companys knew the downside of sealed axle bearings. In pulling axles, whether in yards, partscars, or r/e ends coming in build, it is very hard to find nice used 37+ year old sealed bearing axles that are not chewed. Have been pulling sealed bearing axles for over 20 years, & the good claim rate has always been low. Tapered axle bearings, on the other hand, seldom seize. Unless one has been bent from being twisted (major torque) or hammering a curb, one will usually never need to replace a stock tapered axle bearing axle. That said, given enough torque & traction, there is a point to upgrade to HD aftermarket versions. Got Posi? :3gears: Roger
BTW, the 2nd pic posted is of a '64-66 Buick cast 8.2 rear. The bolt on coil spring retainers & the single rib on side of the housing make it an easy ID. Got Posi? :3gears Roger
