So, diff chatter after filling with Lucas 75w-140?

[Pupp]

Maybe completely off beam here but chasing my tail trying to 'fix' a grouching/chattering/popping noise that originally I had down as prop joints, then driveshaft joints; now all renewed with nothing obviously 'wrong' - noise still there definitely prompted especially on tight slow turns, but evident also on slow and straight pull aways and coming to stop. Wheel bearings seem fine.

Have idled the car in 1st, 2nd and 3rd on axle stands with no roughness or bad noises (bottle twitching too much to spin up more than that). No gearbox roughness, release bearing noises and it seems to be more diff/rear-end. Have coasted it out of gear too with nothing - will find somewhere flat to try shoving it around tomorrow with engine off.

Now, it only *seems* to have developed since a diff oil change over winter - Lucas 75w140 synthetic went in and google says many use an additive too. Could it really be an oil issue rather broken/worn mechanicals? What works well in a BTR if I dump the Lucas? Castrol? Anyone got an exploded view of a BTR?

[SILICONEKID350HP]

Pupp said:

Maybe completely off beam here but chasing my tail trying to 'fix' a grouching/chattering/popping noise that originally I had down as prop joints, then driveshaft joints; now all renewed with nothing obviously 'wrong' - noise still there definitely prompted especially on tight slow turns, but evident also on slow and straight pull aways and coming to stop. Wheel bearings seem fine.

Have idled the car in 1st, 2nd and 3rd on axle stands with no roughness or bad noises (bottle twitching too much to spin up more than that). No gearbox roughness, release bearing noises and it seems to be more diff/rear-end. Have coasted it out of gear too with nothing - will find somewhere flat to try shoving it around tomorrow with engine off.

Now, it only *seems* to have developed since a diff oil change over winter - Lucas 75w140 synthetic went in and google says many use an additive too. Could it really be an oil issue rather broken/worn mechanicals? What works well in a BTR if I dump the Lucas? Castrol? Anyone got an exploded view of a BTR?

I use the lucas 75/140 with no problems .Lucas is massive in the USA and very popular.

Edited by SILICONEKID350HP on Monday 22 April 23:19

[Pupp]

SILICONEKID350HP said:

I use the lucas 75/140 with no problems .Lucas is massive in the USA and very popular.

Thanks Diaz, that's really why I used it but every diff will be clutching differently according to wear and tolerances, and the stuff has its fair share of critics . Q is whether just change it again or add a friction modifier, or do both...

[Hoofa]

I just used Morris oils in the diff was advised don't bother with additives ,

[carsy]

I reckon if you are getting noises like you are, an oil change will make little difference. I suspect it may be time for it to come out and have a coat of looking at. Having said that for the price of a litre and a bit of oil you could try changing it first, although i bet it still ends up coming out.

[Sardonicus]

I would try changing to another brand 1st like Castrol Syntrax Limited Slip 75W-140 don't expect instant miracles though the noise you may be hearing is the clutch plates shifting/groaning and the additives need time to soak into the plates friction material it's sometimes that simple IMO, my GKN moaned a little on full lock until I changed to the Castrol and that was over 4 years ago no problem since, Ford Capri's with the LSD fitted had a similar complaint that only having the right additives added or proper LSD oil would cure, of course as Carsy mentions it may be time for tear down attention.

[Pupp]

It's an interesting one... just spoke to John Reid at Grantura/Readman and I had hardly finished telling the tale when he said 'and it's clanking is it...?' Reckons it happens quite a lot and a fluid change should sort

He also recommended Morris Lodexol 80w/140 fully synth so I'll whistle some up and see what's what

[Pupp]

Just to tidy this one up for anyone tripping over the same issue; a fluid change to the Morris product did indeed sort it

[Bassfiend229hp]

Pupp said:

It's an interesting one... just spoke to John Reid at Grantura/Readman and I had hardly finished telling the tale when he said 'and it's clanking is it...?' Reckons it happens quite a lot and a fluid change should sort

He also recommended Morris Lodexol 80w/140 fully synth so I'll whistle some up and see what's what

Good to hear that he was right (as was Sardonicus) as I'm hoping to get him to do my gearbox later this year.

Phil

[brett84]

I used the Redline oil in mine and it made it quieter
http://www.redlineoil.com/product.aspx?pid=44&...