Best for diff rebuild/exchange?

[Gully]

My GT6 has a 3.63 diff built into a 6 bolt case. When I first had it rebuilt by a local firm (from the 3.27 original ratio) it was lousy, with apparently no effort to set the pre-load and the quality of the supposed 'good used' pinion somewhat questionable - see below! I then had it rebuilt through Robsport and whilst it wasn't cheap, I've had no issues since - quiet and leak-free. Their go-to chap is more used to Stag diffs, but clearly understands Triumphs.

Gully

[Pete Lewis]

there are some good clues about tooth marking  the rights wrongs and  what to do to correct it in most Triumph workshop manuals

the daft thing is a hypoid having an offset contact  has a much longer tooth contact and is designed to be quieter than a inline bevel pinion 

maybe triumph thought otherwise   Ha 

[trigolf]

4 hours ago, Gully said:

I then had it rebuilt through Robsport and whilst it wasn't cheap, I've had no issues since - quiet and leak-free. Their go-to chap is more used to Stag diffs, but clearly understands Triumphs.

Gully

So come on Gully,

Don't keep us in suspense ! - Who do Robsport use  - one man band or larger company ?

Gav

[Gully]

1 hour ago, trigolf said:

So come on Gully,

Don't keep us in suspense ! - Who do Robsport use  - one man band or larger company ?

Gav

I understand it's a one-man band - certainly seemed to be the case as they had to check when he had a slot to fit my diff in. I don't know who, though.

Gully

[steveweblin]

Tony Lindsay Dean used to supply diffs.  I think is now winding down.  Have seen that he is selling off some stock

[trigolf]

18 hours ago, steveweblin said:

Tony Lindsay Dean used to supply diffs.  I think is now winding down.  Have seen that he is selling off some stock

There seems to be few transmission companies that recondition classic diffs (of all types) etc.  Has anyone ever used Hardy Engineering Transmissions in Leatherhead to rebuild a Triumph diif successfully ( i.e. quiet)?  I see they give a 12 month warranty on all jobs.

Gav

[trigolf]

On 20/11/2020 at 13:42, trigolf said:

There seems to be few transmission companies that recondition classic diffs (of all types) etc.  Has anyone ever used Hardy Engineering Transmissions in Leatherhead to rebuild a Triumph diif successfully ( i.e. quiet)?  I see they give a 12 month warranty on all jobs.

Gav

Judging by the lack of comments - I take it that no one has used them in recent times ?

They seem to get good testamonials from various classic owners with diff issues...

Gav

[Nigel Clark]

I'm getting 2Spec in Coventry to build a strengthened 3.27 final drive with helical gear LSD for my 2.5 litre GT6.

Paul Hughes at 2Spec is s Triumph enthusiast. He's also building me an 1850 Dolomite gearbox in a 3 rail casing with J-type overdrive, which (I hope) will fit easily in the GT6 and cope with the torque of the 2.5 engine.

www.2specgroup.co.uk

Nigel

[trigolf]

On 23/11/2020 at 20:29, Nigel Clark said:

I'm getting 2Spec in Coventry to build a strengthened 3.27 final drive with helical gear LSD for my 2.5 litre GT6.

Paul Hughes at 2Spec is s Triumph enthusiast. He's also building me an 1850 Dolomite gearbox in a 3 rail casing with J-type overdrive, which (I hope) will fit easily in the GT6 and cope with the torque of the 2.5 engine.

www.2specgroup.co.uk

Nigel

That's interesting Nigel. Let us know how you get on !

Gav

[Nigel Clark]

7 hours ago, trigolf said:

That's interesting Nigel. Let us know how you get on !

Gav

Will do!

Nigel

[RogerH]

On 20/11/2020 at 13:42, trigolf said:

There seems to be few transmission companies that recondition classic diffs (of all types) etc.  Has anyone ever used Hardy Engineering Transmissions in Leatherhead to rebuild a Triumph diif successfully ( i.e. quiet)?  I see they give a 12 month warranty on all jobs.

Gav

Hi Gav,

I have used them to rebuild a TR4A gearbox and Overdrive that worked well afterwards.

I have not had a Diff rebuilt.

If you use them and you are in a rush for the diff to be returned tell them up front. Otherwise it sits in a queue - they can get quite busy.

 

Roger

[trigolf]

15 minutes ago, RogerH said:

Hi Gav,

I have used them to rebuild a TR4A gearbox and Overdrive that worked well afterwards.

I have not had a Diff rebuilt.

If you use them and you are in a rush for the diff to be returned tell them up front. Otherwise it sits in a queue - they can get quite busy.

 

Roger

Ok, thanks for the info Roger. I'm surprised that no members in the Greater London area seemed to have used them, as they have been around for a long time.

Courier costs are expensive when you have to ship a diff from the South coast,where I am !

Gav

[Roger K]

I used Hardy's years ago when Dave was still alive, as we both had Healey 3000s and Dave was a very successful racer of his.  Good company but haven't dealt with them for years.

Roger

[RogerH]

6 hours ago, trigolf said:

Ok, thanks for the info Roger. I'm surprised that no members in the Greater London area seemed to have used them, as they have been around for a long time.

Courier costs are expensive when you have to ship a diff from the South coast,where I am !

Gav

Hi Gav,

a chap on the TR Reg forum had his TR6 diff rebuilt here   DIFF.

The result was perfect.   Is Westbury too far form the South Coast

 

Roger

[GT6M]

be ware of re building, or getting  olde diffs re built

can have the best possible contact patterns, drive an coast,

an it,ll whine or howl

can ev a contact pattern miles off on drive, but ok on coast an its fine

coast generally dont get much stik, only in over run or reverse

 

generally if the bearing pree loads, sides an  pin ones, are slack then it,ll whine wid load,or on overun,or both

as load will shift the contact areas, moer so if diff worn.

a 1 thou shim on a criticly worn cw will move pattern alot in some instances

 

Butt, if it whines on drive an goes quiet under load, then it needs either pin ajusted, or cw adjusted, or both.

as movement has shifted contact to a quieter spot.

 

Non of which can really be determined with any certainty untill its in car.

even when try,n t,run a diff under load on yer bench, ye just cannae get the loadings that happen on the road.

patterns are a guide only on olde units { some new,ns too ive found }, real life shows ye this.

 

So just cos its noisey, dont mean folk aint tried their best

Ive spent 30+ odd hours on some, a thou here, or there, , diff hights, diff side gaps all to ne good at all

and cw/p look ok, but they worn oot, so best for banger race,n or a weigh in.

 

some diffs, are v v quiet wid a 20+ play in mesh { OE 3-4 thou } but they clonk on tek up an over run

 

Ive had brand new CW/Ps sent t,me t,re build, and just cannot get a same pattern on all teeth

some are near bottom, some are near middle,some are near top, same too for the coast

an CW runs true, so ne run oot,  what ye doo wid them , send em back,

get another, its same, spend another full week at it, still noisey,

show folk the contact patterns, all owa the spot

{ t,get a different  in pin height, then its a full diff strip doon, t,get a side thrust, a little easier, just tek the CW oot, but then ye gotta split the bearings, on a tr type, its a pain }

 

also, what looks good wid  nee load, is not same as with load

an cant say for certain that a 2 shim will be ok to put it where it should be as on the other ye just did, cos in reality it wont show same contack patch

due to wear on both cw/p that really cant be seen wid yer eyes.

 

some can be done in 1/2 hour, and they look fooked

some look good and are impossible t,get right

 

so dont always blame the bloke trying his best if he,s spent a full week onit, for little money

as would any body on here work 30+hours , stink,n of oil, dutty finger nails  an hands for a week on a diff for 40-80£ wage,

 

I spend it, as its a hobby

 

 

M

 

[Pete Lewis]

well said  Marcus 

Pete

[Clive]

11 hours ago, GT6M said:

be ware of re building, or getting  olde diffs re built

can have the best possible contact patterns, drive an coast,

an it,ll whine or howl

can ev a contact pattern miles off on drive, but ok on coast an its fine

coast generally dont get much stik, only in over run or reverse

 

generally if the bearing pree loads, sides an  pin ones, are slack then it,ll whine wid load,or on overun,or both

as load will shift the contact areas, moer so if diff worn.

a 1 thou shim on a criticly worn cw will move pattern alot in some instances

 

Butt, if it whines on drive an goes quiet under load, then it needs either pin ajusted, or cw adjusted, or both.

as movement has shifted contact to a quieter spot.

 

Non of which can really be determined with any certainty untill its in car.

even when try,n t,run a diff under load on yer bench, ye just cannae get the loadings that happen on the road.

patterns are a guide only on olde units { some new,ns too ive found }, real life shows ye this.

 

So just cos its noisey, dont mean folk aint tried their best

Ive spent 30+ odd hours on some, a thou here, or there, , diff hights, diff side gaps all to ne good at all

and cw/p look ok, but they worn oot, so best for banger race,n or a weigh in.

 

some diffs, are v v quiet wid a 20+ play in mesh { OE 3-4 thou } but they clonk on tek up an over run

 

Ive had brand new CW/Ps sent t,me t,re build, and just cannot get a same pattern on all teeth

some are near bottom, some are near middle,some are near top, same too for the coast

an CW runs true, so ne run oot,  what ye doo wid them , send em back,

get another, its same, spend another full week at it, still noisey,

show folk the contact patterns, all owa the spot

{ t,get a different  in pin height, then its a full diff strip doon, t,get a side thrust, a little easier, just tek the CW oot, but then ye gotta split the bearings, on a tr type, its a pain }

 

also, what looks good wid  nee load, is not same as with load

an cant say for certain that a 2 shim will be ok to put it where it should be as on the other ye just did, cos in reality it wont show same contack patch

due to wear on both cw/p that really cant be seen wid yer eyes.

 

some can be done in 1/2 hour, and they look fooked

some look good and are impossible t,get right

 

so dont always blame the bloke trying his best if he,s spent a full week onit, for little money

as would any body on here work 30+hours , stink,n of oil, dutty finger nails  an hands for a week on a diff for 40-80£ wage,

 

I spend it, as its a hobby

 

 

M

 

Marcus, do you have or know of a source of the curved shims? 

[Pete Lewis]

those being the  thrusts for the planet gear end float ???

Pete

[Clive]

39 minutes ago, Pete Lewis said:

those being the  thrusts for the planet gear end float ???

Pete

I don't know😬

My friend does a few diffs, but can't find the curved shims anywhere, and has just run out of reclaimed ones. There must be  supply out there, somebody said a ford shim looked similar, but I have no idea. If anybody has a bright idea etc, it would be handy.

[Pete Lewis]

there must be something close enough , these are the only semi spherical shim/thrusts   all others are flat 

Im suprised there  is wear as only slow moving unless you give it the beans on ice and get high speed one wheel spin #

in normal drives they dont turn much unless you go nuts on the swindon or hemel  magic roundabouts !!!

Pete

[Clive]

4 minutes ago, Pete Lewis said:

there must be something close enough , these are the only semi spherical shim/thrusts   all others are flat 

Im suprised there  is wear as only slow moving unless you give it the beans on ice and get high speed one wheel spin #

in normal drives they dont turn much unless you go nuts on the swindon or hemel  magic roundabouts !!!

Pete

Last one was gone, others paper thin. Some not much wear. Odd really. Unless they were worn from one worn/one new tyres, that sort of thing

[Pete Lewis]

but thats still slow speed rotation of the planets,  theres nothing odd as most used a coppr /bronzed thrusts  

let blame GL5 oils   Ha 

Pete

[trigolf]

17 hours ago, GT6M said:

some can be done in 1/2 hour, and they look fooked

some look good and are impossible t,get right

 

so dont always blame the bloke trying his best if he,s spent a full week onit, for little money

as would any body on here work 30+hours , stink,n of oil, dutty finger nails  an hands for a week on a diff for 40-80£ wage,

 

I spend it, as its a hobby

 

 

M

I can't disagree either Marcus.  

As already stated, all the remaining core stock has already been rebuilt several times. So, I struggle to understand what the point is of getting new C/W+P remanufactured, if not ALL the correct shims are available NEW - even to reconditioners, what real hope have they got to produce a quality item ? Surely someone has got a solution to this problem....

Gav

[Clive]

1 hour ago, trigolf said:

Surely someone has got a solution to this problem....

Gav

I fitted a subaru diff in my spitfire. A bit extreme, but impossible to break. I have tried.

[GT6M]

New shims are available, CW sells em,
BUTT mostly for TR/Sals type

 

they 2-4 times as thick as the GT/Spitty types

butt, worn oot TR shims, are a good fit

but, need a good few, as they not all same size whenst worn

 

like the yans on oor cars,

always  1 will wear oor faster than the other, some times there npwt thea, esp if its a fibre type

niva iva use thee,s for any re builb, they be gone prity quick

 

and the shims aint got be a slack fit, regardless of what the book says

the bearing cups aint smoothe, its ridged, so shim sits on high bit

efta a wee while its bedded in, an as slack as a laydee of the nights money box,

 

they need tapped into spot

and t,mek em last a bit, drill 4 wee wols in em t,get moer oil into em

 

think rimmers an the other spots sell em

 

failing that, get yer self some PB sheet  an mek yer own

ye got the moulds on the diff yer use,n

all thats needed is a bigg bolt an a nut

put shim between carrier an gear, an tighten up

 

best if its heated first, as it,ll mek it easier t,bend.

med loads this way, so simples
 

Keep saying it, but dont change yer oil yer ask,n for trouble

should be changed at least yance a year, ep if yer no use,n it, or it,ll end up like thee,s pics

 

M