Hey guys so i just got my 86 iroc-z i picked it up for cheap because the guy thought that the rearend was blown out.Well i got it home and jacked it up to see what was going on and well the nut and washer flew off the pinion and so the driveline was just sitting there rotating lol idk if the gears inside are good havnt had the time to look i was just planning to get a new rear end,reason why is the first couple threads on the pinion are all messed up and i found a nut to try and put on and it doesnt even want to start so i was just going to look for a rear end.Everything where i am located which is Pendleton Oregon Northeastern Oregon anyhow my car has the rear disk brakes dont know what gears or anything but all the rear end i find are drum. Unless i drive like 200+ miles just to get a rear end which i really dont want to do and i know its down gradeing and i dont want to do it but can i swap a disc to a drum??? I dont know what to do guys please help i really like this car and it's got potential but my selection is very limited around here.I dont know about swapping gears really i have done it but i dont know id rather get something i can just bolt in and not tear apart.

 

Welcome to TGO.

Yes. Check below for more info:

https://www.thirdgen.org/forums/tran...-10-bolts.html

JamesC

 

So would it be a straight bolt up or what?? would it be easier just to change the gears out? I was told that i got to change the porprtioning valve if i was to go to a drum which i really dont want to do.Help please guys i want this rig moving and not sitting in the back yard lol how it is right now i have it up for sale because i can't find anything and dont feel like screwing with it.Unless i can just bolt a drum rear end in and go or something.

 

Why not just get the rear end with the drums, and swap your rear disc brakes over to it? I'm not sure but I would not think it would be that hard to do...

 

You can bolt the drum rear end in and go, though there are a few issues: Without swapping the combination valve the bias won't be correct, you'll need knew parking brake cables, and if the rear end has a different gear ratio than the original, you'll have to swap in new drive and/or driven gear to make the speedo read correctly.

Changing gears is not for the faint of heart. A detailed explanation is in the link as well as info pertaining to the comments above.

JamesC

 

The link above provides info for that as well: modification of the axle flanges or Ed Miller's kit, both of which require axle removal.

Good luck with your project.

JamesC

 

Looks to have a coolant leak from the thermostat area. Im in Tri-Cities that isn't to far from pendleton. I have a drum brake 3.42 rear end I would let you have for cheep. Send me a PM if interested.

 

I could probably help you with the axle removal too if you wanted to swap over your disc breaks. Busy schedule between school and work I would have to see. Just pulling the axles is pretty simple.

 

alright so i took the differential cover off and got the numbers off the pinion 14085343-13-42-7 5/8 so i figure the 13 is for how many teeth are on the pinion and the 42 is how many are on the ring and the 7 5/8 is my rear end size if im wrong correct me and it is a limited slip.But my center console which the vin does match the car vin says it would be a gu4 which is 3.08 gear ratio and limited slip in my year which with a gu4 the pinion is the same 13 teeth but the ring is a 40 teeth and what the numbers on my pinion are stating is that its a gu5 which is a 13 pinion and 42 ring with a 3.23 gear ratio again correct me if im wrong Ive never read these numbers before so either my rear ends been replaced or my center console is lieing to me.Help please because if its the 3.23 and i get a drum rear end cant i just swap gears for gears and put it all back together.

 

He also needs a filter on the crankcase breather. Lots of dirty air is going into the oil. Those plug wires need to be re-routed a lot better.