4200 drive train backlash....

TimR

Member
Messages
924
I after some input as to the the seriousness of this backlash...I personally find it intrudes when driving the car but others have assured me it's normal...!
Car is in 2nd gear. Opposite wheel is not moving.

 

Zep

Moderator
Messages
2,422
I after some input as to the the seriousness of this backlash...I personally find it intrudes when driving the car but others have assured me it's normal...!
Car is in 2nd gear. Opposite wheel is not moving.

That is a good bit more than mine, but there is generally some movement before the locking starts.

I think the lash in the diff should be different from backlash in the drive train. One is the movement between the wheels which is the diff action, the other will be when both wheels move together and will show the lash between the pinion and the crown wheel on the diff. This would be evident with both wheels in the ground, clutch out and trying to push the car against the stationary engine. Is there movement then?
 

MC_Bob

Junior Member
Messages
77
That looks normal for diffs, but the noise suggests there is issues rather than normal play.
For what its worth, my last 2 way diff had severe backlash, and I just waited for it to break. 4 years of drifting and clutch kicks and it never got worse. Needs attention but doesnt strike me as something thats going to develop overnight.
 

TimR

Member
Messages
924
That is a good bit more than mine, but there is generally some movement before the locking starts.

I think the lash in the diff should be different from backlash in the drive train. One is the movement between the wheels which is the diff action, the other will be when both wheels move together and will show the lash between the pinion and the crown wheel on the diff. This would be evident with both wheels in the ground, clutch out and trying to push the car against the stationary engine. Is there movement then?
I see what you're saying.. the "pushing it' test you describe doesnt isolate the clutch as the origin....? And the diff freeplay shouldnt be felt as drive is interrupted briefly to engage the next gear, surely ?
 

TimR

Member
Messages
924
. Needs attention but doesnt strike me as something thats going to develop overnight.
By this you are saying..."it wont get worse over night" , ? Or it didnt happen overnight..?
The car is relatively new to me so Id say it was there before I bought it. It wasnt picked up on during a PPI, and McGraths have insisted "they all do that sir"..
Its going back to them next month..I will press them further...
 

Zep

Moderator
Messages
2,422
The push test won’t isolate the clutch but the clutch springs are going to be pretty sturdy, and that will not clonk, it will just be a springing motion. If you have a clonk, that will be your play.

Have you been out in another manual 4200 and was it different to yours in terms of shunt?
 
Last edited:

Oneball

Member
Messages
1,261
I thought it looked normal too.
Obviously no experience of 4200 but it looks pretty normal to me too. Although I think it sounds like a fair old clonk. Videos can be deceptive but I wouldn’t expect that much of a noise.
 

MC_Bob

Junior Member
Messages
77
It didnt get worse at all, but wasnt normal.If the video was with it in neutral, the issue is down to halfshaft play or play in the diff itself.
 

boomerang

Junior Member
Messages
274
The way you do this now, makes you feel the added play in every part between wheel and pinion/Crown wheel.
That means: Play in the splines between wheelside CV joint and halfshaft, play in the CV joint itself, play in the splines of the halfshaft to the diff side CV joint, play in the diff side CV joint itself and finally the play between pinion and crown.
In my experience most of the play is found in the CV joints and splines of the halfshafts.
If this much play was found ONLY in the diff (backlash), it would be a very noisy one.
Especially idiot starts from standing, cause splines and CV joints to become "loose"
And extra wear of course in the differential bearings/pinion/crown.
A Maserati owner does not need that behaviour though, so we do not have to fear any of this..... ;)
 

TimR

Member
Messages
924
Not sure how hard to pursue the issue tbh..
Its normal...? Great. Hang on...my car is as loose as a goose & thats great ? :rolleyes:

The noise does have some ominous overtones but Im afraid I just have zero experience with what Im dealing with. It could be anywhere in the drivetrain.
The noise might help locate an issue though too...so great. Its fooked ? :rolleyes:

:D
 

Oneball

Member
Messages
1,261
I’ve got my Merc in the air. I’ll take a video. Will give you a comparison bet it’s roughly the same amount of movement