whitt1

My Tahoe has a 10 bolt rearend with a Auburn Pro differential and GM performance gears.It's managed to survive my 449/515 hp/tq supercharged engine,but now I've switched to a 4L80E transmission and want a go with a 4.56 gear,will the 10 bolt take the abuse?

GWTFI

There are Impala SS running LOW 10's, in the 10.0x range that are pushing 800+hp thru built 8.5's. What usually gives up is the crappy Auburn posi. Most of the fast Impala guys are running Eatons. To answer your question directly, the most likely failure if you have one will be to lose limited slip and be a peg leg, if you upgrade the carrier to an Eaton, that will help immensely.

You can view the fastest (that will post timeslips) at:

http://dan.esteban.com/impalass/ReturnTopET.asp

Kelly Rosato

blacktransam

iTrader: (13)

can one of these be put into my t/a?

GWTFI

Well, yes and no. I've researched it quite throughly, and heres what I've found thats same/different.

The F-body rear has a 4.75 x 7 bolt pattern, The B/D body rear is 5 x 5.

Most B body rears are disc brake, but are only set up for 3 channel ABS. So if you don't have traction control it should work ok. I haven't found out yet how many teeth the F-body uses.

However, the D-body has 4 channel ABS compatibility, but is a drum brake rear only.

And you'd have to have the F-body brackets welded to the B/D rear since the B/D uses Upper/Lower control arms and the F uses Lower control arms and a panhard bar.

So it can be done with a bit of planning and not cost anywhere near as much as putting in a 12bolt or a 9". And the strength difference between the 12 bolt and a 10.5" Ten bolt is minor. The 12 bolt is a 8.75" ring, the 10 bolt is 8.5".

Hope that helps!

blacktransam

iTrader: (13)

i'm gunna have to work on this idea and do a bit more research

whitt1

I don't know if it makes any difference to someone planning a conversion but my 10 bolt equipped Tahoe has both ABS and Traction control.

taqwache

hey dude, i have also done a ton of research on this also. forget about the impala axle it would be to hard to install. GM put 8.5s in f-bodys from 71-81. here are the pros and cons.

pros

1. these have the same bolt pattern as all f-bodys do.

2. i found out that the LS1 brake mounting plates will bolt right up.

3. these cars were leaf sprung in the rear so there is only two brackets to cut of. the impala axles center section has built in mounting brakcets that cant be removed.

4. there is hundreds of camaros and f-bodys in junk yards and the entire 8.5 can be bought for $200 or so.

5. they are almost just as strong as 12 bolts. i have ran one behind my 700rwhp 69 camaro for 6 years and never broken anything in it.

6. every aftermarket rear axle company supports them and you can find everything to make them stronger for cheap.

cons

1. it is a bit shorter then 4th gens since they dont use as much wheel backspacing. you can just use spacers or get a different backspacing in the rims.

2. no torque arm mount. this is ofcoarse the biggest most important problem there is. with some good welding skills this can be fixed.

3. you will also need to weld lower control arms and a pan hard mount.


I have though alot about this progect. the thing is that i already have a strong 8.5 with 4.10s that can out of my old 1980 Z28. when i bought my 69 camaro the first thing i broke was the orignal 8.2 that was in it. then i just cut the leaf spring pearches off my 8.5 and welded them to fit the 69s leaf springs. i ran this for years and never broke it so i am a beliver. now it is time to try to fit it in the 02 to keep the tradition hehe.

blacktransam

iTrader: (13)

this interests me more than n e thing i have heard so far. I think it's time to go junkyard shopping and get maybe 2 of them. One to practice on and one to use.

JimsZR2

The rear axle found in the 94-03 ZR2 p-up's and Blazer's are 8.5in 10-bolts. They also are the correct bolt pattern, have disc brakes, ABS, and a gov-loc.

taqwache

yup they sure are. altough these are hard to find and junk yards want alot of money for them since they are on newer vehicals. i am not sure how close the wheel width is on them eather. they might be closer. also they usually have that weak locker that has problems breaking.

taqwache

tell us what you find. i am going to remove the one out of my 69 and see how hard it is going to be to weld a torque arm mount to it. that is the only problem i see with the swap. everything else is gravy.

taqwache

here is a thread i started a while back of the idea of just removeing the torque arm and useing latter bars to make the swap easyier. check it out



https://ls1tech.com/forums/drag-racing-tech/122483-why-not-get-rid-torque-arm-better-60s.html

99power

Hi! Guys just to let you'll know the 80's Buick GN came with a 8.5 also. but neet to ck the axle flange,may be different

taqwache

yup they sure did but they also have the same problem with the built in upper conrtol arm mounts. also these are very, very rare for 2 reasons. 1. because of how rare turbo buicks are already and 2. because people that usually have hot rodded monte carlos, regals, cutlasses, and other g-bodys usually ****** up all the avalibale ones as a bolt in replacement for the factory 7.5. i think it sucks how GM acually put these behind a turbo V6 car that usually does not have that much low end torque but would not put it behind a LS1/LT1 car that has tons of axle breaking low end torque. go figure.

99power

[QUOTE=taqwache]yup they sure did but they also have the same problem with the built in upper conrtol arm mounts. also these are very, very rare for 2 reasons. 1. because of how rare turbo buicks are already and 2. because people that usually have hot rodded monte carlos, regals, cutlasses, and other g-bodys usually ****** up all the avalibale ones as a bolt in replacement for the factory 7.5. i think it sucks how GM acually put these behind a turbo V6 car that usually does not have that much low end torque but would not put it behind a LS1/LT1 car that has tons of axle breaking low end torque. go figure.[/QUOTE
Yes I use to be one of those,'79 chev malibu with Lt1

taqwache

cool car dude. what did it run?

99power

Hi 13's with a cam,(what the guy I got the engine told me) intake,headers,true dual with vforce mufflers and strip inside plus those car weight around 500 lb less than the 93-on camaros.sorry sold the car(wife said to much money to finish it)So here I'm building a 99 Silverado.(wife doesn't mind) go figure.

03tahoe

I HAVE 4.56 PRECISION GEARS IN MY TAHOE AND I AM HAVING HUGE PROBLEMS. I ONLY HAVE AN INTAKE, CHIP AND EXHAUST AND I LOVE THE GEARS FOR AROUND TOWN DRIVING BUT I HAVE BURNED UP 2 SETS WHEN I HOOK ON TO MY TRAILER. I LOVE THE GEAR RATIO BUT I AM IN THE PROCESS OF LOOKING TO "BEEF" UP THE REAR END TO HELP. IM NOT GETTING ANY HELP FROM PRECISION OR THE DISTRIBUTOR ON THIS. THEY BLAME IT ON THE GM REAREND BEING TOO WEAK.