Page last updated 27 September, 2011

Technical Questions - Drivetrain
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Date asked

Question Answer

26th August 2011

By Philip Roper

I have just finished replacing the UJ's on my 1600M and am now putting the driveline back together... however I don't know what is the best grease to use on the spline of the half shafts, can you suggests one?

I always use Moly (Molybdenum) Grease - simply as that's what is normally found in most CV Joints these days and the friction reducing properties help reduce wear on the splines.

14th August 2011

By John Kievit

I've had a recurring problem with vibration from the rear of the car. It kicks in around 50 mph. I greased the u-joint in the prop shaft which helped a bit but didn't solve the problem. I asked a mechanic to have a look and he suggested that if the prop shaft were about an inch longer it would straighten the shaft and reduce the possibility of whipping. I have to admit that when I was reassembling the car and reinstalled the prop shaft I was a bit surprised that the gearbox end of the shaft didn't slide onto the pinion very far. It makes me wonder if I have the right prop shaft. Is this a TVR part and do you know what the length of the shaft is supposed to be?

Follow up by John on 21st Sept 2011

The mechanic dropped the differential about 5/8 of an inch and the vibration disappeared.
Makes me wonder if my car is not riding a bit high. But I don't know what would cause that.

You may remember also that I was having all kinds of carb problems. I bought a new carb which fixed that problem.

The propshaft length is something that could occur if the prop was modified (i.e. shortened at the front) to fit to a 5 speed gearbox, then fitted to a 4 speed car. Apart from this, have you checked the run-out of the rear hub flanges. I have a new hub to fit to the 3000M due to an out of true flange. This happens when the wrong method of flange removal is used (I'm working on a new tool for this as it's almost impossible to remove these without it).

Hope that helps - if it's the hub see my homepage as they are available as a unit now with bearings/hub complete.

18th December 2009

By Milko

Hi there.
I have a late M and found a fix that you might like to publish ragarding the UJ flange wear. When the UJ 's were turning inside the flange the space between UJ and Flange increases. Even when I took new UJ's they were turning inside the flange eating more of it in time. What I did is very simple and works perfectly!

Heat up the flange. Use flux to clean and solder some standard plumber solder to add some material.
The hole will be too small for the UJ now but the solder itself is not a hard material. When mounting the new UJ you will press the solder out that was too much. Then you have a perfect fit and the Uj will never spin again inside the flange. So simple as that.
Clean, Heat, Add flux, Solder and remount and use some more force to press the solder out..

Worked perfectly for me and is much cheaper than new amateur flanges that (name witheld) supplies. My one did not even fit. Not even with extra adapters and stuff supplied later on.

Hope this works for more people!



p.s. I wish I had made some pictures but I did not. But the case is simple right? It really works and the lead is strong enaugh to keep the UJ bushes in place and is soft enough to be pressed out what was to much.
Now we dont need any of the stupid flanges anymore that need converters.

Thanks for the tip Milko!

25th April 2007

By John

My car has ben garaged for a while and I think the clutch plate is seized. Clutch pedal moves just as usual with the same resistance I would normally expect. That rules out a hydraulic/cable issue?
I know some people say that its good to get it onto a quiet sloping road and engage first gear,roll down the hill and start the engine but it isn't so easy to get my car on to the road.
My car is in my garage and to get it out I must reverse it down a steep but short slope and somehow reverse it back up another steep and short slope at the entrance of my driveway (exhaust scraping slope!) and then reverse it through 90 degrees up a hill onto the road. Not easy! I need it in situ really.
So some others say run the engine till warmed up with the clutch pedal down. Stop the engine and repeat a few times.
Do you have any experience of trying to unseize a clutch please? Your opinion would be most useful.


Follow up on 11th May 2007

Tried the axle stands technique - no luck, not initially anyway.

Left my car overnight on the sloping driveway in first gear with handbrake off, nose pointing uphill. When I went to try to disengage first gear with the engine off and put clutch down, I could feel the car slipping backwards bit by bit before I had actually got it into neutral. Started the baby and I drove it up the slope into the garage no problems!

So maybe doing that, having the weight of the car on the slope working against the seized clutch overnight just finished off what had been started with the axle stands technique?

Moving onto your question regarding the seized clutch, there are a few things you can try to free it off - two of them you've already described. From what you describe I take it that although the clutch feels normal, the car won't go into gear with the engine running, but does ok when switched off?

The best method bearing in mind your garage position would be to put the car on axle stands and get an assistant to press on the clutch pedal - then you will be able to see if the clutch fork moves on the gearbox (at the other end of the clutch cable). If so then try the following:

Jack up the rear of the car both sides. Start the engine with the car in say 4th gear, raise the revs to approx. 1000-1250rpm - try the idle speed adjustment screw on the carb to allow it to idle at this faster than normal speed. Keeping the clutch pedal PRESSED fully down, the rear wheels will be spinning as they are off the ground. Now with your other foot, apply the footbrake lightly at first and progressively press harder. If the clutch plate frees off the revs will rise quickly so you know when it frees. Make sure the car's well supported and can't fall off the axle stands/jacks!!

If this method doesn't work, you will have to somehow take the car out of the garage and try this method again, but instead of braking, try letting the jacks down simultaneously (2 assistants required). This is a bit tricky and also may involve the car shooting forward if it doesn't work first time - so make sure there's enough room for this just in case. This method is a bit harsher but shouldn't do any damage.

Hope that helps you sort it - they can seize up quite badly after just one winter - especially like the damp weather we had a few weeks ago.

9th March 2007

By Dennis Schils

My name is Dennis i'm from Belgium i've bought aTVR2500M a couple of months ago the car is completely restored but i have problem.
When driving and putting load on the car makes an inoing noise from the back,when i release the throttle she makes a clonkering noise from back also when i put here in neutral when on speed she makes a clonkering sound.
On hard acceleration the car seems to shake or gibber a bit.
Could this be the diff ?
I have a salisbury diff.
I have seen pictures of these diffs being attached to chassis on the lower backend mine isn't could this be the problem or do you think it could be something else.


Follow up by Dennis on 10th March 2007:

Dennis from Belgium again thanks for your quick answer to my diff question.
So i've checked the propshaft nothing wrong with that but now i've tried to remove the salibury diff now another problem.
Between the diff and the half shaft flange there seems to be an alloy spacer of about 1,5 cm on both sides.
The diff seems to be stuck between the halfshafts and these don't seem to have any space left to slide in and out.
Are these spacers suposed to be there or did the previous owner make a mistake in the rebuild.

Many thanks for your email. I'm not entirely sure whether the noise/juddering you describe is caused by the same problem, however the Differential can "clonk" when worn or can juddering. First take a look at the propshaft to make sure the Universal Joints are in good order and aren't about to fail. Make sure it's mounted to the diff. and gearbox correctly, and that all fixing bolts are in place. If so, the vibration could still be caused if the propshaft is out of balance.

If the propshaft is ok, then check the diff. mountings to make sure all fixings are in place. if so, check the half shafts (one to each rear wheel) and again make sure the universal joints are ok including the flanges (see diff. page on the website). Access to a ramp will be of great help to check this if you can find someone who can help you.

The salisbury diff is very strong but as they are old can suffer from internal wear or need an overhaul....I suspect one of the above will be the cause)s_ of your problems, but for a clonking noise always look at the exhaust system and handbrake cables also - very common for noises from these on M series cars.


M-Fix follow up:

The spacers I'm almost certain are standard only on the Salisbury diff models. To remove the half shafts you need to undo the circlips on a U/J and move it out of the yoke. If you have to remove the diff flanges, take off the wheel, brake drum, shows, then undo the drum fixing nuts to the hub. Undo the half shaft rubber coupling boot clip and slide out the brake backplate/hub/outer half shaft complete. This will then allow you to undo the 4 diff flange bolts and take off the inner half shaft.

4th March 2007

By Dean Legg

Do you know if the Taimar axle is TR6? The Taimar could have either the TR6 or Salisbury Differential fitted, although all cars from chassis number 3955FM had the Salisbury unit. Half shafts and rear hubs/discs were TR6, but the hub carrier was TVR's own cast alloy unit.

Easiest way to tell is to look at my Technical Manual in the chassis section, full restoration page. The first photo is the chassis and diff - this is a Salisbury unit. The TR6 unit has a much less substantial frame "hanger" - quite easy if you take a look under your car.

5th August 2006

By Martyn Harvey

My car has a Chevrolet 350 cu ins engine and has been driven for 25 years as
far as I can tell.
The TR6 diff has worn out and the previous owner gave me a good Jag V12 diff
to use. Is there any way of removing the TR6 diff without removing the
body? As i research this conversion, it is looking a bit more complicated
than i thought. I'm assuming a number of people have done this differential
swap. Is there detailed information on the web?

Follow up on 6th August 2006

Do you have any pics of your "trap door" and/or any instructions how you
removed the diff this way?

The only way to remove the diff without body removal is to make a hatch (see the technical manual pages) like I have. This can be removed and with the rear screen removed it will allow the diff to be hoisted out.

The swapping of diffs is quite common but you'll need the diff. cradle for the Salisbury diff plus all relevant mountings, plus change some of the drive components, like the 1/2 shaft flanges and prop shaft. Could be quite a task to get all the bits you need - probably the best way is to stick a free wanted advert up on my website? Not sure if any website has a full instruction section on how to fit this, that's why I am trying to crwate the online manual!



There is a photo of it on the Interior section overview - it's simply an aluminium plate with an "X" shaped crossmember made from angle aluminium riveted on the underside. After cutting out the storage tray fibreglass this screws down in its place.

To remove the diff. remove the rear screen, the aluminium hatch, then unbolt the half shaft flanges, the propshaft, then use an engine hoist to support the diff in its cradle (see chassis restoration page for photos of the diff in its cradle). Undo the four cradle to chassis bolts, and then hoist out the diff.

Sorry no full instructions as yet.

22nd March 2006

By Jonathan Edwards

Can you tell me the standard ratio for the Salisbury diff on a 3000M? If it
helps, chassis no is ****FM. (T reg)

Also, is there an easy way to check it is the Salisbury and not the TR
unit? I hear the Salisbury is able to take a bit more power.

Please find attached a photo of the
Salisbury diff. - it is easy to distinguish from the TR6 type as it has a
pressed steel rear cover. The TR6 one is cast. The Salisbury diff is
stronger as it was fitted to Jaguar and (I'm told) aston Martins in the
60's & 70's. Parts are rare for these - especially the TVR made diff
flanges to allow the half shafts to attach to the diff. Last time I was
quoted ?350 for one!

As for the ratio, I think it is 3.31:1 but not sure if the LSD and non LSD
type share this ratio.

20th March 2006

By Carl Toellner

Hi, are there differences with the prop shaft between Triumph TR and Salisbury rear end?
Or is it the same item?

Yes the propshafts were different - part numbers are different in the M Series Parts Catalogue (available from David Gerald Sportscars Ltd - see my links page).

11th July 2005

By Olivier Loyez

The differential front mounting plate of my 3000M is damaged: the metal is sheared-off near the chassis mounting point. I believe it can be welded again, but I need to remove it first. I intend to follow the sequence:

-disconnect prop shaft at differential end (four bolts)

-disconnect mounting plate from diff (4 screws)

-undo diff to chassis bolts (2 bolts)

Access is difficult, but I am hoping not to have to remove the exhaust.

Have you done this before and if so is there any major difficulty I should be aware of?

Update on 13th July 2005:

A quick update on my original query: I managed to remove the front mounting plate of the differential without removing the exhaust or the differential itself. The tricky part is to undo the nut on the diff shaft (holds the flange connected to the prop shaft) as it is difficult to prevent the wheel from turning as you try to un-tighten it.

Yes your sequence is ok, but don't forget the half shafts need to be removed also to take out the diff. unit.
The diff is very heavy and requires either the bodyshell to be removed, or the rear window and a special access hatch fitted to the inside rear storage area (see the website in Technical Library section, Interior, Overview).
You will need a small engine hoist or similar to lift it out without straining!

31st March 2005

by Christian Proud-Diaz

My car runs very well at that time, the only trouble I have to fix is an oil
leak on the rear axle. Might be the seals between differential cage and propshafts... What is your opinion? Is it complicate to fix? Do I need to remove arms, etc. ? Bolts and nuts are very rusty and I'm afraid to break them on removal...

The rear diff seals can be changed with the diff. but the half-shafts need
to be removed obviously, which means the hub assembly has to be removed
also. This unbolts from the aluminium hub carrier with 6 nuts, and you may
also have to split the half shaft universal joints depending on how much
room you need. It is easier to have the diff. removed from the car to fit
new seals, but this is a problem as the whole bodyshell has to be removed as
the diff is lifted out of the chassis. I have made an access panel in the
M-Fix TVR so diff. removal is now possible just by removing the rear screen,
halfshafts and propshaft.

You will also need to undo the flange nut and extract the flanges on the
diff with a puller to get to the seals - so an air ratchet would be needed
for the nut removal also. If it is just the propshaft seal you need to
replace then that is less trouble, but awkward as it's right in the middle
of the car....again ramps, a pit, or lift would be the best way to do this.

The job is quite involving and would certainly be easier if you have access
to a garage pit so you can stand while working under the car, or
alternatively use a proper garage ramp.

Hope this gives you a little idea.......I will try to do a full article on
this very soon.

7th June 2004

by Duncan

I noticed recently a squeak coming from the rear end under load
(but not when freewheeling, nor specifically going over bumps - ie, not
probably suspension related ) which has developed into a 'clonk' when the
clutch bites.

On a rolling road earlier today for a tune up, we noticed the car rear end
slewed slightly outwards (towards the o/s). A quick inspection of the
Salisbury diff suggests an oil leak somehere, but as it's rather dirty and
oily, it's hard to see exactly where and since how long ?

I need to get het car up on ramps for a better inspection - any view as to
whether the problem is likely to be a drive shaft, u/j and or diff (or of
course, a combination?). How easy is it to replace the u/j's as the ones
I have do not have grease nipples.

Sounds like a UJ is working loose in a drive flange or half shaft...or possible the needle roller bearings have broken up and cause one part of the shaft to move before settling under power. Check these first, but possible the clonk is the crownwheel/pinion, or spline wearing out on the propshaft to pinion, or a halfshaft sliding joint (unlikely). The UJ's can be removed (sometimes with trouble) by removing a pair of opposite circlips and tapping the roller bearing inwards to offset the spider, then tap back the other way using a drift on the spider or nylon mallet on the halfshaft. Once both bearing cups protrude enough the spider can be wiggled out (make sure the wheel is off the gound to allow the halfshaft to rotate separately to the diff flange which will aid removal.
19th June 2003

by Nigel Hucker
I need to change the UJ's on the drive shafts of my Taimar.
I am having problems removing the hub from the rear hub carrier.
I have removed all the brake parts, and the six nuts from the studs which secures the hub to the carrier.
Have tried jacking the back plate away from the hub flange using Threaded bar and nuts, but it just won't budge. any tips?
Did you know that there's no need to remove the rear hub carrier to change the U/J's?
But it is a lot easier if you take the hub out to do the inner joint.
I'm assuming that you've undone the rubberboot on the halfshaft sliding joint so that the hub & outer halfshaft are extracted as a whole piece?

As you have the braking system removed and the six nuts removed then the only thing keeping it in place is rust/corrosion or maybe some gasket sealant which could have been used (to prevent corrosion!).

The easiest way to loosen this up would be to bolt the wheel back on and use this as a lever - by rocking it side to side it should release the hub. Failing that you could try using a slide hammer on the wheel studs (see the bodywork tools section on website), the shock should free it after a few attempts. I seem to remember having some trouble removing the hubs myself due to some corrosion.

Finally if all else fails the best method would be to remove the complete halfshaft (outer first by undoing the flange to the diff), slide off the inner shaft from the sliding joint.
Now the outer half shaft is free you can remove it from the outer u/j which will leave the yoke of the hub in place. Use a block of wood and a lump hammer to knock it out (making very sure the car is safely supported and won't fall on you).