help! 3rd new diff and still knocking
 

Hi guys

Back last year the back of the car started knocking at low speeds when turning the wheel. This was diagnosed as the rear diff, so I got another off ebay and had it fitted and all was well again.
A few months ago the knocking came back but this time worse than before, so took it to a specialist who again diagnosed it as the rear diff. This time they ordered it. Diff came and they fitted it, drove the car away and over 30mph the back of the car felt like it was dragging and the diff was making one hell of a whining/groaning noise.
So this was sent back to the people they got it off and they sent a replacement diff, which was then fitted again.
All seemed ok, until 6hours after picking it up from the garage, im potering around tesco carpark looking for a parking space and i hear the knocking start again when I turn the wheel. Not as bad as before but still audiable.

Now, surely i cant have been so unlucky as to have all these rear diffs go, there must be another issue. Could the centre diff be gone? someone also mentioned backlash? (dont know what that means)

Have you guys got any ideas on what it is?


Big thanks if anyone can advise

surely if the rear end was dragging it would mean incorrect ratio on the diff maybe???
do you still have the original diff? if so count the teeth on crown and pinion and divide the 2 giving you the ratio i think yours should be 3.9 but if its anything like the bugeye sti its more likely to be 3.545 instead of 3.9 as qouted in subarus parts book. :nono:

hope this helps but dont take anything i say as gospel as im certainly no mechanic. :thumb:

hi mate i had a similar problem only started knocking when going slow as when i was pulling in to park,it never did it when car was cold only after about 20 minutes it was the centre diff hope this helps Jim.

I dont have the original rear diff unfortunetly:(

Yeh the diff that was dragging was taken off the car and replaced with another one. It is the latest diff on there that is knocking now.

Could it be that the centre diff is taking it out?

Have they matched the diff to the code on the gearbox?

Yeh they did match it.

Does it still sound like a rear diff problem then do you think?

Don't rely on the codes they were wrong for my car. This may be a daft question but how do you know it isn't the rear struts knocking?

Good point, I will have to have a look to see if its that. Didnt really think about them

What model, what year, what gearbox, what diff?
Give us the maximum available information on your car, there are several different gearboxes, several different diffs, lots of different models, lots of configurations that wont work etc and my crystal balls broken.

Tony:)

The fault has been found:) and it was nothing to do with the diff. I did my own bit of investigating after reading previous threads on here.
Old man took it up today to tell them what i'd found because I was in work, but he forgot the part name, but i think he is reffering to the bushes on the rear.

So hopefully this will now cure the fault once and for all

Just in case your not aware the rear struts on the newage models are a VERY common problem. If they are really bad they will actually stick so just try lifting the car by hand if it doesnt drop on its own they are screwed.

If you would have given all the cars info to start with we may have solved it quicker ;)
ALWAYS post what your car is (usernames mean nothing, you could still own a classic scoob with it), and we can tell you what faults are common to said vehicle.

Tony:)

Will do mate thanks:)

Turns out that it was the drop links

haha hope it hasnt cost too much. good time to buy some alloy droplinks though :thumb: