Thread: 2nd opinion on my diff whine

they changed the carrier bearings?

ask them
what preload the pinion bearings were at prior to them re-installing the center and was that within specification.
if it wasnt within specification did they replace the pinion bearings or at least reset the preload
ask them what the face height of the pinion was set to and did they check that they used the correct DTI reference block for that model of the rover diff.

when hes answered that inquire how you go about setting the backlash if the pinion has movement in it.

should either get you some interesting looks OR some interesting answers.

Sounds to me they don't know what they are doing! I have rebuilt several diff myself and have had no problems. Do you have the Salsbury diff? if so most people have no idea how to set them up properly nor do they have the tools to do it correctly. If you are certain you had no noise in the diff before hand then they have done something wrong and it will destroy your diff. The noise is generally caused by the miss alignment of the gears and is generally cause by faulty / worn out / or incorrectly fitted bearings. If there is insufficent pre load on the bearing this would also cause some noise. I would be demanding they they fix the problem at there cost as it couldn't have been fitted properly. Tim

yer, iv been back but they say it can not been anything they have done, and that they are the specialists at drive lines, its a wolf rear diff, they say they noted that the diff oil had water in it, witch im not going to argu as i had been 4wding day b4 it went in, BUT it would of done at most 100km round trip with that oil, and i change oil at most times to often, im one for spotless oils

i think im just going to pull it out my self and set it up, i have the tools and the specs to go,

They have buggered up I'd say. I have found these diffs rather forgiving my self. I have only done about forty odd and some using secondhand parts. None of them whine. The pinion bearings can collapse and they still don't whine.
It will need to be set up properly.
The problem is not likely bearing preload unless they missed one.
Whine is usually pinion depth and or tooth contact.
I'd suspect the second.

they say??? they allways cheak there work with the blue tooth paste for the contact

so could it be as simple as back lash??

a drive line specialist who cant set up a diff without it whining isn't much of a specialist.

ID ask for the spec sheet for the install done on your diff then to see the certification of the person who did the install of your diff.

how'd they go answering my previous questions.

might be time for a call to consumer affairs.

I'd almost be willing to bet that the tooth contact pattern will be out and it will be showing up with incorrect face contact so the pinion bearings need reshimming which they wont have the correct tools to measure and set so they havent done that. What they've probabley done is shuffled the carrier across to get the correct generic backlash setting of 10thou (If they bothered to do that) and then blued it to make sure that its got something near to the right contact patch size.

The blue paste know as bearing blue checks the tooth contact between the pinion and the crown wheel. the back lash is measured with a dial gauge.

Wolf diff - is this the flipped P38 diff in the rear of a Defender?

Could be that your specialist is in the clear, its the diff that's rubbish.

Sounds like yours is already cactus. Have a search - the whine, premature wear, countless warranty replacements, it's all in various threads in here.

In my experience you're wasting time & money fitting a locker, the diff isn't up to it. I mangled four cw&p sets before giving up & fitting Salisbury. The trophy set has cw teeth torn out at the root.

To give you an idea of how weak these things are, my last P38 diff that let go was during a recovery - snatching someone else. The strap's just fine..

Regards
Max P