306stang

hey guys just took her out for a spin to find a clunking sound whenever i decelerated without brakes.
It seems to decelerate a bit faster than my 98 mk8 which i'm not sure is normal or not. it's an auto aswell.
Any thoughts??? im hoping its not my rear end failing!!!! and if this helps any, i feel the clunks more than i can hear it.
feels as if i'm getting pulled backwards every time it clunks, just a SLIGHT pull, kind of like when you run over rocks or something.

some suggestions before i go rebuilt it, unless i figure out wether its an 8.8 or not! if its a 7.8 i'll just throw in an 8.8. lol, never did check considering i'm pretty much keeping it stock.
Anyone know a tell tale difference between an 8.8 and 7.8 visually?

thanks alot!!

mjr46

check u-joints and or tranny mount

1989convertible

u-joints tight?

306stang

how do i go about checking my ujoints???
as well as tranny mounts?

i also read about the drive slack maybe having some slack? but i'm sure that'd only affect acceleration right?

mjr46

make sure the rubber is not broken on mount/ detatched from metal portion that it's glued to and as for u-joints.....jack car up and put it in nuetral and grab yoke on driveshaft and hold it with one hand and the driveshaft with the other hand and twist them opposite ways trying to feel for play..and make sure all driveshaft bolts at flange are tight

HACKGT350

86+ have 8.8's in them unless you did a 4cyl conversion then you have a 7.5 not a 7.8 i didnt even know ford made a 7.8

306stang

yeah 7.5 my bad lol i was debating which to put, forgot what it was.
I've googled some of the problems as well, seems people just have faulty ujoints when you get clunking in deceleration.
I'll check it all in the morning and if that's it, hopefully have it fixed in the next few days.

thx guys!

HACKGT350

u-joints are easy and cheap and its a great place to start if you wanna do the shot gun aproach to this. either way if they have never been replaced its not a bad idea to do it. i know autozone sells brutforce u-joints for 15 a peice which isnt bad

PJC Racing

+1, and if both of these check out you may want to check for excess pinion to ring gear play.

306stang

just replaced both ujoints today with some heavy duty ones.

thx for all the help guys. she runs too smooth now [8D]