I have made a deal to purchase a complete rear assy from a 25th anniversary 91 Z-28 . It has a 3.42 gears with a posie diff. This is where I need some advice. The unit has disk brakes and the original that is in my car has drum brakes. Will my IROC wheels from the rear that are on the car still fit the new disk brake unit. I am aware that the front and rear on my car will not swap with each other because of a different offset and inner center hub length. I just want to know if the rims from the rear of my 86 will work with the the disk brake setup. Are there any other concerns that I will need to address. Thanks Guys

 

i have an 87 iroc with rear disc and the iroc wheels on them

 

i believe ther is a difference between the rears... as far as the brakes goes.... the rear will bolt in and all of that stuff fine.... but the brakes is where u might have the problem.... it has something to do with the rear caliper changeover in 89 to the pbr rears and not working w the older style.... IM NOT SURE... make a post on thirdgen.org or maybe somone else will answer whose on this board....

 

yeah everything should just bolt right up!

 

Thanks guys. The part I am buying is a complete rear housing,diff ,axels ,disk brakes everything,. I am pretty sure that the units will swap out ok . My concern is will my rear wheels that are on my drum set up now fit right when i put them on the disk brake unit I am going to install. Thanks

 

No problem with your Iroc wheels fitting the 92 rear with disc brakes. No changes on 3rd gen wheels made to fit disc brakes. I am using 87 IROC wheels on 89 rear with the the 11.655 rotors & PBR aluminum calipers.

 

im not sure,i have a disk brake rear off an 86 IROC that i plan to put in place of my drum brake rear '87 and i noticed that the disk brakes had a shim on them...im guessing for wheel clearance. the wheels that were on it were not iroc wheels though. only 1 way to find out for sure....TRY IT!

 

The .187 thick shim was installed on iron drum brake cars to maintain the same spacing after the change from aluminum rear drums ( they were thicker). They are not necessary on rear disk brake cars.