Lt77 Gearbox Noise

Defender91 · Nov 10, 2020

Hi,
I appreciate that this has been covered before,but my lt77 is making a whirring noise in 1st,2nd,3rd and 5th. I've only just noticed it but I did do a load of sound insulation at the weekend so it might have been going on for a while.
Had a look at other forum posts, and it would seem to be the layshaft bearings are at fault.
It's not hugely loud, probably about the same as the turbo whine.
What are people opinions on this? Likely to go bang tomorrow or do they usually last a while?
Also, is it a feasible job to replace them?
Thanks

mick 1986 · Nov 10, 2020

Defender91 said:
Hi,
I appreciate that this has been covered before,but my lt77 is making a whirring noise in 1st,2nd,3rd and 5th. I've only just noticed it but I did do a load of sound insulation at the weekend so it might have been going on for a while.
Had a look at other forum posts, and it would seem to be the layshaft bearings are at fault.
It's not hugely loud, probably about the same as the turbo whine.
What are people opinions on this? Likely to go bang tomorrow or do they usually last a while?
Also, is it a feasible job to replace them?
Thanks

Having just stripped my LT77 and rebuilt it, I would advise you strip it and replace the layshaft bearings, before one fails like in my case. I was lucky as the case wasn’t damaged, but it damaged the input shaft and layshaft. The cost to rebuild mine, was around £550-600 all in. I spoke to Ashcrofts who wanted significantly more than the website would lead you to believe for a recon box, which wound me up enough to do the job myself. I struggled with a few bits, but @jamesmartin advised on the bits I struggled and completed it.

Defender91 · Nov 10, 2020

Hi, thanks for replying, I've not done a gearbox before but I've done both diffs and the engine so it's the next thing to do. What's worrying me is how long it's been doing it, it's been so noisy in there until recently all kinds of things could have been going on and I wouldn't have been any the wiser.
When doing the gearbox, are there special land rover tools which you can't do it without? I looked at doing the transfer box once but seemed you needed a entire kit to set it up properly.
Thanks

jamesmartin · Nov 10, 2020

Defender91 said:
Hi, thanks for replying, I've not done a gearbox before but I've done both diffs and the engine so it's the next thing to do. What's worrying me is how long it's been doing it, it's been so noisy in there until recently all kinds of things could have been going on and I wouldn't have been any the wiser.
When doing the gearbox, are there special land rover tools which you can't do it without? I looked at doing the transfer box once but seemed you needed a entire kit to set it up properly.
Thanks

aslong as bearings remain in tact its not such a problem as gear teeth still have the proper mesh its when they fail and shafts then arent running true gear damage occurs ,t/box needs no special tools only for removing and fitting bearings,setting bearing preloads only needs feel

payydg · Nov 13, 2020

Defender91 said:
Hi,
I appreciate that this has been covered before,but my lt77 is making a whirring noise in 1st,2nd,3rd and 5th. I've only just noticed it but I did do a load of sound insulation at the weekend so it might have been going on for a while.
Had a look at other forum posts, and it would seem to be the layshaft bearings are at fault.
It's not hugely loud, probably about the same as the turbo whine.
What are people opinions on this? Likely to go bang tomorrow or do they usually last a while?
Also, is it a feasible job to replace them?
Thanks

I once drove 800 miles over a few weeks almost entirely in 4th having developed a similar problem a few miles into a trip. Worked fine. If you need to drive try not to put to much force through the lower gears. Obviously needs sorting

Defender91 · Nov 13, 2020

Thanks, good to know it probably won't let go too soon.
Still weighing up the options, I checked with Ashcroft and it would be £600 quid all in for the swap, but they've got a lead time of a month to build one and changing it in potentially -5 doesn't sound too appealing.
I've got to decide whether to put it off until the spring and hope it lasts, or look at fixing it.
Willing to try and do it myself, but I've very little time at the moment so would probably have to be in the spring anyway.
I took it to work today, its barely noticeable when cold but gets quite a bit louder once the oils heated up.

mick 1986 · Nov 13, 2020

Defender91 said:
Thanks, good to know it probably won't let go too soon.
Still weighing up the options, I checked with Ashcroft and it would be £600 quid all in for the swap, but they've got a lead time of a month to build one and changing it in potentially -5 doesn't sound too appealing.
I've got to decide whether to put it off until the spring and hope it lasts, or look at fixing it.
Willing to try and do it myself, but I've very little time at the moment so would probably have to be in the spring anyway.
I took it to work today, its barely noticeable when cold but gets quite a bit louder once the oils heated up.

What oil are you using? It could be that it’s too thin when hot.

Did you actually receive a quote from Ashcrofts with that price on it? Reason for asking is that I thought my exchange would be around £450-500, then I realised they are quoting figures - VAT, and they also charge VAT on your shipping return (not sure they are allowed to do this) but it ended up being over £800 when all was said and done. It’s not worth it, in my opinion.

Defender91 · Nov 13, 2020

I sent them an email, got this back:
LT77 £445 exchange
Core deposit £200
Carriage £60 return
+ VAT
I discounted the core deposit as its refunded.
Worked it out to be around the 600 quid mark without that.
I'm using Comma AQ3 Semi Synthetic ATF , are there different viscositys of gearbox oil?

Lt77 Gearbox Noise

Defender91

Active Member

mick 1986

Well-Known Member

Defender91

Active Member

jamesmartin

Well-Known Member

payydg

Well-Known Member

Defender91

Active Member

mick 1986

Well-Known Member

Defender91

Active Member

Similar threads