Got a rear axle out of a 95 Jimmy 4x4 for my Pontiac (dirt cheap - was sitting in the mud for years) - I think its limited slip rear end but never seen one before to be sure. Was told the ratio is 3.42:1 and spinning it by hand it appears to be - and both hubs rotate the same. Cleaned everything up and removed the cover (10 bolt). Everything looks tight and clean, no moisture in lube or burnt smells. The numbers on the pinion are 12-41-GM-7-5/8 and on the ring gear GM 14085339-12:41-7-5/8. Can anyone confirm whether or not it is a limited slip, or do I need to find more numbers first. Thanks for the help
3.42's are the usual ratio for S10 type SUV 4x4's with a 4.3 engine.And it's likely to be a Gov-loc unless it was changed out in the past. Many dislike Gov-Locs but they can work ok if not worn out.
Thanks guys for the input. Done some further research and it is a G80 "gov-lock" type of axle. Can anyone help with: 1. How to remove the axles as I wish to put new axle seals in before installing. From what I've read, dis-***embly and re-***embly is not for newbies like me and want to make sure I don't do a "Oh dammit". 2. What checks can I do to ensure its still functional ? Again depending what info I've read, the "4x4 and high HP" guys say this gov-lock type is **** and throw it away, but the "good for an old restore" guys say it's a good upgrade to do. My plans are to couple it with a newer T5 behind the original 239 in-line 6 in my 51 Pontiac for improve fuel economy and reliability, not smokin' the tires for 100 feet. Thanks !!!
I personally think those rear ends should all become part of an artificial reef some where at least then they will work right but that being said. Do yourself one big favor, go buy a shop manual for the vehicle it came out of. Not some cheapy thing from Pep-boys but a real shop manual even from the dealer if you have to but I bet you can find one on line some where. But and there is always a but first worry about how to fit it to your suspension. Are you going to have to relocate the spring hangers? I doubt it will be a direct fit. If your a newbie then your going to need to enlist the help of someone who definitely knows what he's doing. If you don't get the pinion angle just right you will be eating up u-joints worse then my German Shepard eats dog biscuits. Not to mention a whole slew of vibration problems etc. Typically you want about 3 degrees of up angle on the rear but your going to need to do a whole lot of figuring and measuring. Do you have the engine and transmission already mounted in the ch***is, if not you need to start there first. Once you get all that figured out then you need to have a drive shaft made. So sorry if it sounds like I'm ****ping on your parade but your getting way ahead of yourself worrying about changing axle seals.
12-41 12 teeth on the pinion gear 41 teeth on the ring gear 41 divided by 12 = 3.4166666666 is a 3.42 Marty McF.
Problem with using it in a '51 Pontiac, while a near bolt-in, it has the wrong pattern for the wheels on it. But the newest near bolt-in with the right pattern is 57 Olds or Pontiac, not a lot of choice out there. Unless your car is a Canadian Pontiac - in that case it will be the same, it won't be any different than using it in a '51 Chevy. I did see, too, a rim on about a 92 Caprice in the junkyard the other day that looked like a full size dual-pattern spare, don't know how unusual those would be but it's also an answer to the problem.
That was the first thing I checked before taking the axle home and the bolt pattern matches exactly - and yes it is a Canadian Pontiac so just about everything good for the Chevy will be good for it. To FNG - if the angles are so critical, then how come people can add 4" blocks without changing the angles, or do they ?? My plan is to try to match the angle of the pinion to the same angle the motor/trans are sitting so the joints have a balanced twist between them. Again any suggestions are greatly appreciated !!
Well you just pointed out a quite commonly over looked thing when ever people lower a car. Most guys concern themselves with pinion angle when they raise a vehicle or do a rear swap but ignore it when it comes to lowering a car. It's equally as important and it also depends on how you lower the car as well that effect pinion angle. Blocks, remounting the rear so the springs are under the axle instead of on top of it, airbags etc. One thing that is prevalent is that typically when you lower a car the angle decreases (straightening out the drive shaft in relationship to the transmission yoke) so this intern puts less stress on a u-joint then when the body is lifted. Just imagine in your minds eye the extremes of your rear suspension travel as the rear goes down the body goes up and the angle increases, as the body goes down the rear gos up and the angle decreases. so less angle= less stress on the u-joint(s) typically the rear joint takes the brunt of the wrong angle but I have seen front joints snap because of too sever of an angle but this typically was in 4x4's
At the same time, you don't want the driveshaft to be absolutly straight either, I think there's a problem with bearings wearing into the u-joint because they don't spin... Mopar musclecars have an engine that's not lined up straight in the bay because of this. Chevrolet put their rearend housings off the the side to get a bit of angle.
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