Jerky driving, "juddery" takeoffs etc.

[ash]

Hey all,

My latest woe is driveline related and it makes the car very unpleasant to drive.
It is most pronounced when cold.

To start with the clutch judders when taking off, unless an inordinate amount of slip is used.
Secondly when off the throttle, approaching an intersection, or at slow speeds (carpark etc) the whole car gets this resonant bunny hopping motion going.
Its almost like there is some play in the gearbox/clutch/driveshaft/diff.

A new clutch was fitted when I did the engine (not many kms done since then) and the gearbox has been rebuilt.

Thoughts?

Cheers
Ash

[wot179]

Did you machine the flywheel?

[MeFB]

Check your engine mounts first, after that its gearbox and / or engine out for a good look at the clutch.

The clutch plate might have some oil on it from the rear main seal or it could have been bent when reassembling. The flywheel can become warped if the old clutch was slipping and generating a lot of heat (might now need machining).

Lets hope it's the engine mounts.

[ash]

Yeah flywheel machined and in perfect condition.
I've had the inspection plate off and can't see any oil, certainly no leaks.

Engine mounts are also new.

[Harv]

Ash,

a) Check clutch free play at both pedal end (1/8”) and slave end (5/64”).
b) Foot on brake, handbrake on, bonnet open. Engage first gear and let clutch out gently (ride it somewhat) then pull clutch back in. Repeat. Have assistant stand at side of car (NOT IN FRONT!!!) and watch the engine - it it rocks excessively (or clunks) you may have busted a mounted (or had a shitty new one fail prematurely).

Cheers,
Harv.

[fingers]

Check ya unis mate ...........Fingers

[Craig Allardyce]

I had the same problem years ago and went thru the usual oil on clutch, rear main, engine mounts, etc with no luck.
Mine was ok in forward gears but shocking in reverse.
All of my problem was down to driveline slop and I ended up doing a fair bit to get rid of it i.e.

Uni's
Rebuilt gearbox incl replacing all gears with excessive backlash
Overhaul diff to reduce crownwheel to pinion backlash (replaced planetary gears as they were shot and this was the worst area found)
Reset rear springs and fit helper spring to stiffen suspension and prevent axle windup. One common cause of diff wind up is loose "u" bolts combined with shot spring pads which all leads to the diff housing being grooved out.

I never did it but I've always been sus on the clutch plate damper springs and have wondered how a solid clutch would go. Atleast it would eliminate another possible cause.

Hope this helps somewhat.

Cheers