Screetching/cutting noise from 5-speed box

I have this in a car which recently got a new 5-speed box installed. But it only happens in 5th gear. Very noticeable and unpleasant.
Trying to get exact info on what box it is. Probably a T5

Somebody forgot to fill it with oil?

Would that cause the very audible noise on just 5th?

There is a bit of nouse on 1-4th but thats normal nouse I think.

Perhaps I should add that I have only done three 15 min drives, of which 10% were in 5th, for 2 reasons, the country roads rather than motorways, and the noise on 5th.

Definitely check the oil and the alignment of the transmission to the bell housing. Use your finger to outline the gap, if any around the bellhousing. A bolt cold be loose causing a misalignment internally.


My T5 installed in xk150 10 years ago also has extra noise in OD. Pretty noticeable with Windows rolled up. What kind of sound proofing have you installed between top of tranny and body. A couple inches of foam pretty much takes care of it.

I have a T5 in a 3,8 E ots since 2006. No problem. Likewise in a 140 ots. And 3 different/other 5-speed boxes in other Es, and no such problem.

Cant check the oil level, or metal particles in it, until I get back to my summer house in about a month. Will put it on s lift and also check alignment as suggested.


I now know that they filled the box with ATF.
Can this cause such a noise in 5th, rather than all gears?
I will check for misalignment when I there next time (at my summer house, 350 miles S of Stockholm

World Class T-5’s should be running on ATF only. But non-WC T5 shouldn’t, I guess.
Try to check which one is Yours - WC or not.