Drivetrain Backlash...?

[troydv]

Hey guys, I have a BA Mk2 XR6T, 6 speed, 58000km. Has flash tune, injectors, cold air, larger cooler, and valve springs. Approx 270rwkw.

I am experiencing some pretty aggressive backlash when rolling in gear towards a stop. Makes the whole car shudder forward and back, and makes a loud clunk clunk clunk clunk (as what I feel is the drive chain) bouncing forwards and backwards as the cars speed slows the engine. If I am holding the gear stick, I can feel the clunk quite solidly moving the stick. It also makes a clunk when first engaging a gear (think it is diff bushings...?)

Can anyone shed some light on my issues? Universal joints? Tailshaft? Diff? or Gearbox? Or any way I can test to find out?

Any recommendations or help would be greatly appreciated as I am new to this scene. Sorry if this is a re-post, if so refer me to a link? Have looked through and everyone has different ideas. Happy so spend some cash fixing it, I'm just not sure what I am looking for?

Cheers, Troy

Edited 25/06/09 09:48 AM by tab
Title changed

[PHANTMXR6]

Hate to break it too you mate, but there's no drive chain in your car.

There are a few things your drivetrain shunt could be though and you've pretty much listed them all.

First and easiest thing to do is jack your car up and get under the rear of it. With suitable axle stands in place of course.

From there you can check all the tailshaft and driveshaft cv joints. You can also grab the flange on the diff and a driveshaft and see if you can feel any backlash in the diff also. While you're there check all the diff bushes as if they are shagged then that could be your problem as well.

If these all check out ok then it's back towards the gearbox you need to go.

Could be a gearbox mount also. You just need to go through a process of elimination.

Forgot to ask, is it a manual or auto. If it's auto it could be a software issue too.

Edited 03/06/09 01:04 PM by PHANTMXR6

[troydv]

haha told you I was new. It is a 6 speed Manual

Thanks PHANTMXR6 for answering, great advice! Will get under there on the weekend and have a look.

Exactly what I was after, a process.

Cheers

[pezzaxr6t]

ive got the exact same problem mate (bamk2 6 spd) 36k, I had mine on the hoist the other day found no major issues, a very good diff mech told me its most likely to be a number of small thing that make up this noise throughout the whole drive line including gearbox (could have slight wear), but if it helps ever since I lowered my car more I think the noise had slightly picked up so could be CV joints and theres kno real way of knowing unless u pull it 2 bits im told so yeah..

let me know wat u found dude, because I mite have to do somthing bout mine aswell

cheers nick

[XR06T]

when the car is in the air and on stands, get your jack under the diff and raise it slowly. if the diff moves up and down with ease, you rear bush is shagged.

that's the most likely culpurit.

[Corzza]

I give mine a squirt here and there and when I tap off sometimes after wot she kicks as if it were a very hard downshift.

Is this considered backlash through the trans? Mines an Auto

[jdh]

I also have a 2005 BA Mk II (6-speed manual) with this problem. It's more noticable in lower gears (1-3), in these gears it often clunks when downshifting and getting back on the throttle after completely backing off gives the same feeling. I'd be interested to hear more on this.

[dule]

jdh, I think yours is different to the original post. Yours sound like a regular free play in the box / diff / axles that's especially noticeable on manuals in lower gears on low revs.

[jdh]

Ah. Thanks dule.

[Hazy]

hey guys, instead of starting a new post thought I would add to this 1. I have an 03 XR6T ute, and between changing from 1st to 2nd it can have a dodgey clunk to it. its only rarely but was wondering on your point of view or who has had this problem. also sometimes when changing thru to 1st to 2nd, 2nd to 3rd, sounds like the timing is off. dosent flow like it should. what are possible problems with the trans/diff?

Any clues would be awesome!

Cheers,

Hazyco