4th gen rear
#1
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Car: 1990 Formula, 1989 Mustang LX
Engine: Stock TBI 305, Built 302
Transmission: 700R4, AOD
Axle/Gears: 4.10, 4.10
4th gen rear
I'm looking at swapping a 4th gen rear into my Formula. I know it's wider, but how far will the factory wheels stick out of the fender wells? And is everything just bolt in?
#2
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Car: 1992 Camaro RS
Engine: Rebuilt 350 going in after paint
Transmission: WCT5, 7k & counting behind the 350
Axle/Gears: 4thgen disc rear w/ 3.73 Posi
Re: 4th gen rear
I just finished the same swap on my Camaro. My wheels are just inside the fenders when you look straight down on them. I am running the stock 15" Camaro wheels.
Everything is a direct bolt-in, except for the ebrake cables. Depending on how your original ebrake cables are set up will determine the cables you need to match the new rear. Even the "recommended" ones sometimes don't fit either. I have the "right" ones and they don't fit at all. Still trying to figure out what to do with them. Most people don't have problems though.
Everything is a direct bolt-in, except for the ebrake cables. Depending on how your original ebrake cables are set up will determine the cables you need to match the new rear. Even the "recommended" ones sometimes don't fit either. I have the "right" ones and they don't fit at all. Still trying to figure out what to do with them. Most people don't have problems though.
#3
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Car: 1990 Formula, 1989 Mustang LX
Engine: Stock TBI 305, Built 302
Transmission: 700R4, AOD
Axle/Gears: 4.10, 4.10
Re: 4th gen rear
Thanks 92RS, what e-brake cables are needed for the swap?
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 4th gen rear
the formula wheels will stick out a bit farther out past the quarter panel than the 15rs wheel does .
It wont look rite unless u use a 4th gen wheel.
they will be 1.5 inches farther out each side than they are now.
It wont look rite unless u use a 4th gen wheel.
they will be 1.5 inches farther out each side than they are now.
#5
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Car: 1988 Camaro IROC-Z
Engine: LB9 (305 TPI)
Transmission: 700R4
Axle/Gears: 2.73 Positraction
Re: 4th gen rear
I used the 4th gen e-brake cables, with hose clamps to hold them to the stock hard mounts under the 3rd gen body. With some basic adjusting to get the tension right, it was a simple install.
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Car: 80 SE/TTA;88 T/A GTA;86 T/A
Engine: 4.9L Turbo; LT1; empty
Transmission: TH350; T56; empty
Axle/Gears: 3:23 disk; 4:10 disk ; 3.42 disk
Re: 4th gen rear
Formula body with LS1 (98-02) axle :
I used the LS1 ebrake cables and the equalizer up underneath, so that the cables fit like factory, just had to reinforce the sides with some metal, and drill out the center to slide onto my ebrake adjuster underneath. Completely factory fit and finish.
I used the LS1 ebrake cables and the equalizer up underneath, so that the cables fit like factory, just had to reinforce the sides with some metal, and drill out the center to slide onto my ebrake adjuster underneath. Completely factory fit and finish.
#7
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Re: 4th gen rear
It is amazing what you can find when you use the search button
https://www.thirdgen.org/forums/whee...end-stock.html
https://www.thirdgen.org/forums/whee...end-stock.html
Trending Topics
#8
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Car: 1990 Formula, 1989 Mustang LX
Engine: Stock TBI 305, Built 302
Transmission: 700R4, AOD
Axle/Gears: 4.10, 4.10
Re: 4th gen rear
I appreciate the input. 3rdgenmaro, I am well aware of the search button. I did use it but I did not find the information I was looking for. Thanks for the link though.
On another note, I got the rear today and the guy I bought it from says the pinion crush sleeve collapsed and that there is too much play in the yoke. It seemed fine to me. How can someone tell if the crush sleeve is bad? It's also got an aftermarket eaton posi in it, does that take the stock carrier bearings?
On another note, I got the rear today and the guy I bought it from says the pinion crush sleeve collapsed and that there is too much play in the yoke. It seemed fine to me. How can someone tell if the crush sleeve is bad? It's also got an aftermarket eaton posi in it, does that take the stock carrier bearings?
#9
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Car: 1992 Camaro RS
Engine: Rebuilt 350 going in after paint
Transmission: WCT5, 7k & counting behind the 350
Axle/Gears: 4thgen disc rear w/ 3.73 Posi
Re: 4th gen rear
I haven't figured out the ebrake cables yet. I decided to finish up some things on the front end of the car first. Once I'm done with those, I'll get back to the ebrake cables. I'll either have to shorten the ones I have, or modify the 4thgen cables to work.
As for the pinion yoke, you need to check 2 things. Use a dial gauge with a magnetic base to check for any in-and-out play. Then use a dial-type in-lbs torque wrench to check the amount of torque it takes to turn the pinion. The crush sleeve is there to take up any in-and-out play in the yoke, and also sets the preload on the yoke.
As for the pinion yoke, you need to check 2 things. Use a dial gauge with a magnetic base to check for any in-and-out play. Then use a dial-type in-lbs torque wrench to check the amount of torque it takes to turn the pinion. The crush sleeve is there to take up any in-and-out play in the yoke, and also sets the preload on the yoke.
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Car: 1990 Formula, 1989 Mustang LX
Engine: Stock TBI 305, Built 302
Transmission: 700R4, AOD
Axle/Gears: 4.10, 4.10
Re: 4th gen rear
Gumby I would if I had the money. I borrowed an in/lb torque wrench and I measured the pinion turning torque. It was about 8 in/lbs. I know that's not within spec. Should I just buy a rebuild kit and tear it apart or just tighten the pinion nut down? I haven't had the chance to get a dial indicator to check in and out play on the yoke though.
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Car: 1989 Camaro RS
Engine: 305 TBI
Transmission: 700R4
Axle/Gears: 3.23 LS
Re: 4th gen rear
What should I look out for when getting a 4th gen rear end? I heard that 98-02 has traction control and other electronics. I want to make sure before swap. Plus i currently have 3rd gen drum rear want disk. Also what gear ratios did they have and how do you know what the differential has?
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Car: Working on an 85 Camaro.
Engine: Hopefully 383 Stroker
Transmission: Will be a Power Glide
Axle/Gears: Undecided, thinking 411's maybe?
Re: 4th gen rear
I was reading in the link that 3rdgenMaro posted and it seems that the only real reason for changing out to a 4th gen is for the disc brakes. Am I understanding that right? If I am just planning to drag race my car, why not just beef up my stock rear? Please Bash me for not knowing!! But also enlighten me!!
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Car: GTA
Engine: 350 TPI
Transmission: 700R4
Axle/Gears: Aussie 9-bolt/3.27 posi
Re: 4th gen rear
I was reading in the link that 3rdgenMaro posted and it seems that the only real reason for changing out to a 4th gen is for the disc brakes. Am I understanding that right? If I am just planning to drag race my car, why not just beef up my stock rear? Please Bash me for not knowing!! But also enlighten me!!
#16
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Car: 1987 IROC-Z red t-top
Engine: Nothing much
Transmission: I wish t56
Axle/Gears: 9bolt 3.27 4sale
Re: 4th gen rear
to put wider tires too its a cheap mod safer than spacers. would u want 500lbt with a 2inch alm spacers and stickys
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