ALFAGTV6.COM

well i finally found where the thumping comes from on hard acceleration ...seems the rear joint is contacting the body...mind you its only on hard acceleration ONLY.....

when i first worked on the car i installed the new rubber joints for the previous owner....ive read alot of posts about different sized joints and am wondering if its this rear joint that is a different size from stock....what i do know is that the spacer blocks on the transaxle mount are thinner than milano ones if that helps any ...

the gtv6 in question is an 83 "leftover" ballocco if it matters

the question is...what do i do about it?..and how do i correct it?...there were ZERO vibrations or anything abnormal ..smooth as silk EXCEPT on HARD launches...at first i thought it was violent wheel hop

heres a few quick shots a grabbed today

Hi Shortlife,

Have you checked your gearbox mounts?

i didnt do a full inspect of them but they looked to be in good shape..ill get a good look at em tomaro and make sure 1 hasnt failed

the car only has 70,000 miles on it....waiting on a sender for the TS box im putting in

A word of caution to all.
A close look at the transmission tunnel clearly shows where the rear brake lines are located with respect to the drive shaft. On this occasion it's a simple case of bump stop adjustment. End of story.

The other story is not so cute. This is when the donut lets go and thrashes around in the tunnel tearing everything up in sight INCLUDING your rear brake line. Suddenly you are in deep doodoo.

Solution:

Relocate your rear brake line NOW. If you could forecast when your driveline will fail, you would never have to worry about it..

Adjust the snubber, problem solved.

Greg Gordon,
www.hiperformancestore.com

and double check the gearbox mounts... get a tire-iron and try to lift the gearbox from the front beam which holds the de-dion triangle.

I agree the gearbox mounts are important, and often overlooked.

Guys,

You are missing my point here. Check it out :

Simply adjusting the snubber and having the best gearbox mounts in the world aren't going to change a thing in relation to this hazzard.

I repeat. Move the brake line.

totaly agree i will plan on re-locating the line later this year....i want it running on the INSIDE of the car anyway as it seems like the smart location for it

so the snubber adjustment is all that was causeing this?

even if you cut the rear brake line the car will still brake... that is why there are two separate hydraulic systems.

That driveshaftfailure could have been avoided i think, in 99% of the cases the donuts(guibos) die first and that's something you will notice. if you choose to carry on driving while hearing a strange rumbling sound underneath your car, accompanied by a strange vibration, you're asking for it. please realize this is just my opinion, although based on my own experience with alot of 75's.

Shortlife, check the gearbox mounts... snubber adjustment may not be the only thing that needs doing to solve this problem.

anyone care to explain the differences in joint sizes so i can get it out of my mind??

MD, I promise I am not missing the point about the brake line. I chose to limit my post to the cause of the "thumping".

Greg