okay was going under the car check things out and noticed a mount leaking. my guess is a diff mount since its sitting right behind the diff. i first noticed a clear gooey liquid on the ground and a trail that led to the mount then it dripped on my hand. looks like two mounts connected together on the same bracket but no clue where to pull it apart from. has onyone heard of this happening? my PPF was broken so i just welded it together and slapped it back on. car feels a lot better, but the diff mount may have been a band-aide holding everything together when the PPF was going. will i be able to replace it for a decent price? can i just get jimlab bushing and put them in there. what are my options?
kris

 

I don't think mounts have anything in them to leak. It could be something else dripping onto the mount and it looks like it's leaking.

I've never touched the mounts on an FD, but I did on my friends talon, they were just metal and a rubber (which was changed to urethane) bushing.

 

I am pretty certain the rubber diff bushings are in fact fluid filled. To get them out you have to drop the diff as the carrier the bushings are mounted in is bolted to the top of the diff housing. Jimlab says you can drop the diff without pulling the axles and then get the bolts out with a wrench.

 

yeah i was pretty sure that is what was leaking. im gonna probably see if i can rig up the KRIS ghetto mod. i dont know how solid the mounts are(cant be SOLID since they are fluid filled), but as an old honda trick we used to fill in motor mounts with ultra black sealant. allow it to cure for about a day or two and you have a pretty damn hard mount. has some give, but cmon, what the price of ultra black compared to diff mounts of polyurethane?
kris

 

get the aftermarket mounts. they are not fluid filled like the stock ones. its pretty common for the diff mounts to go bad. mine is leaking a bit. it can cause wheel hop if not fixed. the broken PPF is dangerous though you may want to get a used or mazda speed one.

 

after you tighten up... consider this. https://www.rx7club.com/forum/showth...hreadid=191383

 

You learn something new every day.

On a techinical note, why are they fluid filled? To give more cushion? Kinda like the water bed thing, sleeping on water, suspending a diff. on water?

 

They just do a better job at preventing any vibration from making its way through the bushing. Many cars have fluid filled engine mounts for the same reason.

 

I think they're fluid filled to dampen the vibrations. The solid ones will transmit more of the diff gear noise.

Don't forget to change your fuel filter while you have the diff dropped. Never gets any easier to get to.....

 

Oh Heck yeah! We should add that one to the FAQ: Anytime you change the diff bushings replace the fuel filter! Come to think of it, my filter should be almost due...

 

Pettit has a nice set:

SU-PK-DMS TRAK PRO STREET DIFFERENTIAL MOUNTS

Designed for demanding street applications, our kit exactly replaces the stock liquid filled differential mounts and minimizes compliance associated with the stock parts. 80 Hardness approximates OEM part but with slightly greater hardness and superior performance and life. $159.00

 

i just ordered the pettit ones monday, i'll install them later this week and let everyone know what i think. i'm also replacing the pillow ball bushing and toe links at the same time

 

I can confirm it for you. Smashed one wide open on my last FD. Sorry no pics.

FD tip #265455634564: When changing the fuel filter, change the in-tank fuel filter as well.
Part # JE17-13-ZE1 They're only $45 here so should be less than US$25 but they have cost more than a few people their motor. Marked as 13-ZE1 below.



-pete