Rear end help GTS with SR5 DIF???

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Hipcat
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Rear end help GTS with SR5 DIF???

Postby Hipcat » Sat Sep 08, 2018 9:29 am

I'm currently working on a build and ran into an issue. I have a 1987 gts, and I'm in the process of installing a new LSD. I ran into an issue with the tips of the axle being too small of a diameter for the new LSD. To make matters worse when I opened the Diff I expected a spool but found a welded OPEN diff. So now I'm not sure which rear end is in the car, or where I need to go for parts. Please let me know what pictures you would need to help me identify what I have. Thanks in advance!

Hip

aukword1
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Re: Rear end help GTS with SR5 DIF???

Postby aukword1 » Sat Sep 08, 2018 1:00 pm

http://www.dreamsofdrifting.com/ae86/axles/index.htm

you might have a mismatched pair of axles to diff. Kouki Axles need a kouki diff and vice versa. Please check out the link for more info.

Deuce Cam
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Location: AZ

Re: Rear end help GTS with SR5 DIF???

Postby Deuce Cam » Sat Sep 08, 2018 4:20 pm

^ to build on whats said in that link... the diameter of the axle at the splines is roughly 1mm less on the 1985 gts vs the 1986/87 gts.

it sounds like you have a 1985 axle in your car if you bought 1986/87 specific lsd, and the diameter of your axles are slightly too small to fit.

you either need to get another diff or axles to fix...

edit: measure the diameter of the axle with a caliper at spline to confirm - '85 is 24.XX mm, and '86/87 is 25.XX mm

edit #2: exact same thing happened to me when i bought a new cusco rs 1.5 for my old '86 gts... ended up buying brand new late version axles from toyota to make it work... (still have the setup in a different car)

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Hipcat
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Location: Aurora Colorado

Re: Rear end help GTS with SR5 DIF???

Postby Hipcat » Sat Sep 08, 2018 9:05 pm

Thanks for the fast replies. That measurement was what I needed. I’ll check them. Also as a side note the company I ordered from sent me the wrong diff, and since it’s been longer than 90 days I may be stuck with it and have to order a new one. It really stinks.

Deuce Cam
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Joined: Sun Jan 13, 2013 2:41 pm
Location: AZ

Re: Rear end help GTS with SR5 DIF???

Postby Deuce Cam » Sat Sep 08, 2018 9:07 pm

also... sr5 axle has drum brakes while gts has disc. further, one can count the # of bolts that hold the third member (aka pumkin) to the axle housing - gts has 10 bolts and sr5 is only 8