parts and pull it place


buick fanatic
May 26, 2001
hi guys,i'm going to harry's u pull it in pa and i want to get a posi rear with some good gears.are the 3.42 gears good for the n/a motors or should i find something else?another thing i was wondering is if they have a 84 like mine but with the turbo and can get it pretty cheap what all do i need to get besides the turbo,intake,downpipe,computer,etc.any help would be greatly appreciated because i'm going up there tomorrow morning.thanks.
Finding a 84/87 Turbo Regal in a junkyard is almost impossible. If you find one, you would want the entire drivetrain. It's not worthwile to do it halfway. And if you are going to go thru the hassle of the conversion, go with the 86/87 Turbo set up.

A 3.42 is a little on the low side (numerically high) if you car doesn't have OverDrive. Its engine would be turning some high RPM's down the highway.

Buick put 3.08's behind the Turbo V6 (without OD) and 3.23 with the 4.1 (without OD) in 1982 GN's. When the 200-4R OD trans came out in '83 on the TR, they went to 3.42. 3.73's would also be good beind the OD trans.

What trans and ratio do you have now?
hi rich.i got a th-350 trans.i'm going to put the car in my garage later and put a deep tranny pan and a super cooler on and i'll check to see what gears are in the rear.oh i forgot to ask,is the ratio on a tag on the differencial case or stamped somewhere?thanks.
It's stamped on the passenger side front of the axle. The first Three numbers/letters will give you the ratio, The fourth maker and the last three are date made.
These are the first three codes(assembly codes) for 84
Gear Ring Assembly
Ratio Gear Codes
2.29 7.5" 2AH, 2BH
2.41 7.5" 2AJ, 2BJ
2.73 7.5" 2AB, 2BB
3.08 7.5" 2AC, 2BC
3.23 7.5" 2AD, 2BD
3.42 8.5" GTE, GTP, GTJ
and here's the link
well guys i went to the pull it place and it was huge.i spent over 6 hours looking at any buick,olds,pontiac car and guess what.not a one had a posi or any gear ratio above 2.41.the ones that probably did were gone.i asked the guy at the gate about that and he said some guy from new york has been coming down and scarfing them all up.can you believe that i looked at over 200 cars and not one.heck there was only 4 buick regals there and this place is huge.they even seperate the models.kinda bummed me out considering its almost a 70 mile ride just to get there.i got a couple of other places to check so i guess i'll keep trying.
Mark, it just hit me that you have an '84 Regal. '84 and up GM cars have a sticker under the decklid with RPO (Regular Production Option) codes. Look for the G** codes. These are for the rear axle.

G80 - Limited Slip (posi)
G87 - 8.5" ring gear
GU1 - 2.41
GU2 - 2.73
GU4 - 3.08
GU5 - 3.23
GU6 - 3.42
GT4 - 3.73

It makes junkyard hunting a little easier. :)
thanks rich.that's what i did.i printed out all the codes and combinations from 78 to 87.the only numbers that came up was gu1 and gu2.
So what code does your '84 have under the trunk lid?

If you can find someone parting out a Monte SS, they have either 3.42 or 3.73 and many are Limited Slip. (And the 200-4R would go nicely in your car, IMO. :) )
hi code is gu1 and that lists a 2.41 gear ratio.the only other g codes are gq1 and g89.i did'nt get to look at my axle but when you turn one side the other side turns the that would mean that i got a limited slip rear and not a posi right?
i got a update for you guys.i have a 83 regal for parts and it has the 4.1 so i checked the code and its not a posi rear but it has 3.08 gears in question is instead of ripping the whole rear out of the 83 and putting it in the 84 can't i just remove the pinion and gear and the guts out to put in the 84?thanks.
GQI = Rear Axle, Standard Ration (???)
G89 = 7.5" Ring Gear.

"Positraction" is Chevy's brand name for a Limited Slip Differential. You have an "open" rear.

You could swap the ring and pinion gears, but the advice I recieved was it was easier to swap complete rears unless you know how to set the gera's tolerences, etc. Check and see what a local garage or trans shop would wnat to change the gears.
it's deffinatly easier to replace the whole rear axle housing then just the gears.because the gears have to be set up to certin tolerances which would require more time and money than it's hard could it be to change the complete axle?four bolts for the control arms one rubber hose for the brakes and the driveshaft and the shock bolts,believe me it doesn't take long,just make sure you spray some PB BLASTER(which i found to be far better then liquid wrench or any other type of penatrant)on all the bolts and brake lines,and don't forget the bleeder valves on the wheel will have to bleed the brakes after all is said and the way if either of the rears have aluminum drums stick with them and shave some pounds off the rear. good luck!
thanks bill.a friend of mine is going to help me swap them either this weekend or the next.
Originally posted by b4black
GQI = Check and see what a local garage or trans shop would wnat to change the gears.

I paid $200 to get a set professionally installed.
About the same price of the tools to set the backlash/pre-lash & an installation kit. This was the price w/the rear still in the car. I drove it up w/ 273's & drove it home w/ 4.56's:D :D :D

There are diff. tolorences for a street driven car & a strip car.
Strip cars are set up too tight for the street & tend to get real hot.
The insallation kits usaully mention nothing about this.