Did a little cursory searching but was unable to find the answer I was looking for, but I'm curious if the peaks of the rubber "castle bushings"/washers that bolt to the subframe, directly under the differential ears, should be touching the differential or not. For clarification, I've attached a page from the parts manual, and the part I'm referring to is 28-880A, called simply: washer/stop.

In my case, they do not touch. There's probably 1/2" or so when the car's on the ground, and maybe 1" or so when the car is on jacks.

Thanks for any insight, and thanks to anyone in advance, should you go so far as to take a look under your own car in the quest for an answer

 

Just coming back to humbly ask if anyone's got any ideas on this. Any of you got any old and forgotten install/project pics laying around that might have the angle we need to answer this question?

 

Edit : I thought I had an answer, but I don't... Sorry :(

 

my car's on stands now, let me take a look

edit, hope this helps.

 

Thanks, Oscar. It does sort of appear that, in the first photo, the castle bushing's peaks do not touch the bottom of the diff. ears. The second photo doesn't show anything concrete, but it does look like quite a bit of empty vertical space above the bushing.

 

I just noticed this last weekend at the track when I jacked up the SM I was driving by the diff case and watch the diff rise a good 3/8" before the car started moving. I then went over to the 95 street Miata and it did something similar, but not nearly as much. I couldn't see what it would hurt to have this issue on a street car- though on a race car you would think that the diff might get unloaded there when jumping curbs. And that's got to be hard on the case ears when it's reloaded.

 

Truth:

 

Yo Brian I noticed this on my diff when I did the solid diff bushings, I ended up reinstalling the oem mounts then urethaning the mounts then adding some extra urethane on top to fill in the gap abit. Its not totally filled so there's alittle gap.

So far so good. Also I am running an rx7 housing.


-Dean