7.5 to a 8.8


Nov 1, 2009
So I'm looking to buy this '86 mustang that was a four cyclinder but was converted to a 5.0. The guy told me it has a 7.5" rear and I want to swap it out with a 8.8". Is there anything else I need besides the rear assembly(drum to drum) like shocks, u bolts, driveshaft, etc.. Thanks in advance
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the 4 banger tranny isnt a POS like everyone makes it out to be. It rocks if your drag racing since first and second gear are so short.
4 cyl trans is rated for less tq. (240 I believe) and they have weaker internals. Yes they can be used but you can kill one fast.
The 8.8 will bolt in, and the same axles will fit. You may have to mess with the brake line mount and axle vent, but it should all fit.

I have had both 7.5 and 8.8 axles under my 82. The one under it riight now is a 4.10 7.5 in axle that has run high 12's for a couple years.

When you swap, you can pull the axles and then unbolt the brake backing plates, and hang them by coathanger wires. Then just put the new axle in and bolt the brakes and stuff back on. Saves bleeding the brakes and messing with the ebrake cables.
the 4 banger tranny is no different that the v-8 t5 the internals are all the same the only thing different is the input shaft ...the pilot shaft is smaller this seems to be the weak point every thing else is compatible , for all the nay sayers I have seen over 400 hp and 435ftlbs of torq running low 12's in the quarter hold up for over a year now on a 4 banger trans.....depending where the rearend comes from, the lower shock mounts might be a little different , the four cyl cars are center bolt mounted and the ones out of v-8 mustangs are mounted sideways and have smaller bushing....and to keep from wheel hopping need to keep and eye out for a set of quad shocks and mounts or step up and get a set of after market lower control arms , jegs sell a nock off set of southside machine lift bars for a pretty good price...think they are lakewoods....yes you might need to pay some attention to the brake lines
The internals are not the same. They're non-world Class (so are pre 85 v8 T5s) and only rated for 240tq.

Yes they have different gearing (some say better),but they are not the same transmission.
4 banger trannies from 86+ are WC just like the v8 models. pretty much everything Borg Warner made after 85 was WC. To the OP, unless everything from the original V8 car was swapped over I wouldnt bother with it unless you are getting it as a dirt cheap parts car. The fact that the 7.5 rear and the 4 banger transmission are still there makes me feel that other shortcuts have been taken. This will lead to a poor handling vehicle(oxy moron with foxbodies) and possibly a poor running one. Re-sale on converted cars is practically zero and anything you put into the car is considered a wash.

Save your money and look elswhere. Good deals pop up all the time.
Well since the motor in the car now has a flat tappet cam I want to use a 87-93 5.0 and convert it to a carb for the roller cam. I know I need a distributor but I'm kinda confused on which one to get because of the gear and the fact that it is a roller. How do I look for that? I have everything else: intake manifold, carb, ignition box, fuel pump. Anything else I am missing? Thanks.