Hi all,

please take a min to read this as its the story of what ive done so far:

my sierra cosworth is a 4wd converted to 2wd & all was well but the cradle was a 4x4 with the 2wd rubber sat ontop & bolted through it.

After searching on here i purchased the correct cradle from ford & this is where the headache started!

The cradle wouldnt fit as the mount was approx 1-2" too far back & there was no adjusted left on runners.
So i redrilled the alloy mounting that bolts to the t5 gearbox & it all fitted fine....

When i pulled away i had a knocking noise coming from gearbox mount, upon inspection i found that as i had redrilled the alloy bolt on section it now put the bolts that held that on ontop of the gearbox rubber bolts & the heads were hitting on each other when the gearbox was rocking.

A new gearbox mount was fitted along with some cap head bolts that gave me abit more clearance & the results.... All good just a small judder was felt on initial pull away which i put down to the rubber donut as this had been running off centre with the old cradle

A new centre bearing & rubber was fitted last week & i still have a rumble from my tunnel area but only when i pull away in 1st gear????

Any idears????
I tried fitting a vibra technics gearbox mount today & i removed it straight away as it was terrible, when i revved the car the vibration felt inside the car was terrible so ive refitted the std mount. Is this normal?

Could it be the diff mount???
Its doin my head in now as £300 later & many hours on a ramp & i cant suss it.
I have looked at the engine mountings & they seem ok, no movement in the engine when i pull away. I have vibratechnics engine mounts.

Any idears or help would be geat

 

Try and make sure both halfs of the prop are in alignment.

If you have bitsa gearbox mounts the rear of the box may be at a different height to standard and this will put the prop out of line, you may have to use different shims in the centre bearing to get it right.

 

hi mark, yes I did notice the prop angle was wrong so again searched & saw the 2wd has 13mm spacers so I packed some washers to 13mm & got prop perfectly straight but still no joy.

the mount fitted is the same one everyone uses for the 4wd to 2wd conversion, only 1 person upon searching had to red-rill their mount which I find strange & 1 had same issues & fitted a mt75 alloy mounting part & it sorted it (but does same job as re-drilling mine)

gearbox looks level
prop inline
all parts above replaced

I even put the car on a ramp & pulled away but it doesn't do it with no load on the wheels so I applied the handbrake to give it some load & it does it. the centre bearing doesn't move, the rear diff moved up/down & the gearbox wobbled abi but couldn't put my finger on it

every other day im having my car on a ramp to try get to the bottom of it, thing is when it was bodged up with the 4x4 mount it was fine! but the gearbox sat to high imo & looked horrible

from inside car it seems like it in mid tunnel area

 

I've read sometime that this can be caused by high spots on the flywheel, which makes sense as the high spots make contact with the clutch plate earlier.

 

Yer i dont think its the clutch/flywheel as it foedmt judder when releasing thr clutch, its when u apply the throttle from 1k to say 3k with clutch fully out. Doesnt do it in any other gears just the initial load to get the car moving

 

Judder when pulling away can be caused by contamination of the clutch friction plate or front to back alignment of the engine and gearbox assembly. I had a DOHC which juddered terribly after I re-fitted the engine and box. The tail of the gearbox was about 20 mm off to one side. Took ages to spot what it was. I loosened the engine & gearbox mounts, straightened it up, re-tightened the mounts and it was fine after that.

 

If everything is in line you have changed the b/box mount and you are sure as the clutch is good then I would look for a worn engine mount.If the box is making contact to the body its got to be moving somewhere.I say this as I had it with a Manta (lol) years ago.It would only move enough for the box to touch just on pull off between say 2/3 thousand revs.

Also had a slight judder when a couple of gear box bolts worked slightly loose on a mk1.Its worth checking.

 

Have you checked the propshaft UJ's?