3000m drive shaft lengths
3000m drive shaft lengths
Author
Discussion

Erich Stahler

Original Poster:

2,878 posts

287 months

Sunday 2nd October 2011
quotequote all
Does anyone know if the drive shafts on the Salisbury 4HU equipped 3000ms are shorter than those fitted to the TR6 diff equipped car?

My car had a tr6 diff originally but I find with the Salisbury there is almost no travel on the splines.

heightswitch

6,322 posts

267 months

Sunday 2nd October 2011
quotequote all
Erich.
Only through playing around with various options of late I would state that their isn't much difference if any.

If I were you I would measure the width of your TR diff and Salsbury diff from flange to flange. as a fixed diff this will be the only determining factor in terms of overall shaft length. in my opinion their will be enough spline travel to allow the diffs to be interchanged. From full droop to full compression the spline only moves though a 10 - 15mm arc so as long as their is no chance of the splined shaft bottoming out you will be OK.

If you are worried. Disconnect your spring and shock and move the suspension through its full arc to ensure nothing bottoms out.

N.

Erich Stahler

Original Poster:

2,878 posts

287 months

Sunday 2nd October 2011
quotequote all
heightswitch said:
Erich.
Only through playing around with various options of late I would state that their isn't much difference if any.

If I were you I would measure the width of your TR diff and Salsbury diff from flange to flange. as a fixed diff this will be the only determining factor in terms of overall shaft length. in my opinion their will be enough spline travel to allow the diffs to be interchanged. From full droop to full compression the spline only moves though a 10 - 15mm arc so as long as their is no chance of the splined shaft bottoming out you will be OK.

If you are worried. Disconnect your spring and shock and move the suspension through its full arc to ensure nothing bottoms out.

N.
I dont have the TR6 diff so I cant make the width between flanges comparison. I think they are bottoming out on droop though.

GAjon

3,932 posts

230 months

Sunday 2nd October 2011
quotequote all
Erich,

I changed from a TR6 diff to a 4HU and didn't have to make any changes in the lengths of the half shafts, only the flanges were changed.

DavidY

4,489 posts

301 months

Sunday 2nd October 2011
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+1 as GAjon, did the same 'upgrade' and kept the same driveshafts

pumpkin

156 posts

258 months

Monday 3rd October 2011
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The drive shafts on both are Triumph 2000.

GAjon

3,932 posts

230 months

Monday 3rd October 2011
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This might be a dim question Erich, but you havn't got the inboard brakes on the diff have you?

Erich Stahler

Original Poster:

2,878 posts

287 months

Friday 7th October 2011
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GAjon said:
This might be a dim question Erich, but you havn't got the inboard brakes on the diff have you?
Er no!

GAjon

3,932 posts

230 months

Friday 7th October 2011
quotequote all
Erich Stahler said:
GAjon said:
This might be a dim question Erich, but you havn't got the inboard brakes on the diff have you?
Er no!
Well in that case, assuming you are still on the standard drum brake, bearing carrier arrangement they should be OK without any modifications other than the flange change.

Erich Stahler

Original Poster:

2,878 posts

287 months

Saturday 8th October 2011
quotequote all
GAjon said:
Well in that case, assuming you are still on the standard drum brake, bearing carrier arrangement they should be OK without any modifications other than the flange change.
That's the point, the hub carrier castings are 6 mm short of standard thanks to last owner's efforts! At present the splined drive shafts are within 3 mm of bottoming out during travel between compression and droop.

heightswitch

6,322 posts

267 months

Saturday 8th October 2011
quotequote all
Erich Stahler said:
That's the point, the hub carrier castings are 6 mm short of standard thanks to last owner's efforts! At present the splined drive shafts are within 3 mm of bottoming out during travel between compression and droop.
Erich, not quite sure what you are getting at.. I think you mean that the bolt face of the upright has lost 6mm, in essence causing the hub to protrude out of the back of the upright and towards the diff flange by an additional 6mm. In theory if this is the case you could have a lazer cut spacer plate made up to restore the distance. Your other option may be at the jag diff end. sometimes they run with a spacer to make up the distance where the inboard disc was and as such potentially you could machine this down a tad.. Some pics would help I would think your splines would be at greater risk of bottoming out at the horizontal plane though??

Your other option may be to machine 1mm off each of the flanges to bring you 4mm back into play? just a thought!

N.


Edited by heightswitch on Saturday 8th October 11:11

GAjon

3,932 posts

230 months

Saturday 8th October 2011
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Would a spacer like this disc caliper bracket mount give you what you need, from what you describe you have lost 12mm of rear track.

Adrian@

4,420 posts

299 months

Saturday 8th October 2011
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Jon, Surely you mean one like this..




but with more holes and less fuzzy..LOL
Adrian@

GAjon

3,932 posts

230 months

Saturday 8th October 2011
quotequote all
Adrian@ said:
Jon, Surely you mean one like this..




but with more holes and less fuzzy..LOL
Adrian@
Yes, if I'm understanding what the problem is that would do it.

By the way Adrian, I still intend to get my car to you at some point, just need a little motivation.

Erich Stahler

Original Poster:

2,878 posts

287 months

Saturday 8th October 2011
quotequote all
Adrian@ said:
Jon, Surely you mean one like this..




but with more holes and less fuzzy..LOL
Adrian@
That would be perfect! the complete ring with six holes that is, how thick is that ring? idealy I would need a pair that are not much more than 6mm thick.

Erich Stahler

Original Poster:

2,878 posts

287 months

Saturday 8th October 2011
quotequote all
heightswitch said:
Erich, not quite sure what you are getting at.. I think you mean that the bolt face of the upright has lost 6mm, in essence causing the hub to protrude out of the back of the upright and towards the diff flange by an additional 6mm.
That is precisely what I mean, the spacer does sound like the perfect solution.

The 3 mm travel on the splined shafts is with the spacer that replaces the inboard disk removed.

Adrian@

4,420 posts

299 months

Saturday 8th October 2011
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This ring is 10mm....Adrian@

Erich Stahler

Original Poster:

2,878 posts

287 months

Saturday 8th October 2011
quotequote all
Adrian@ said:
This ring is 10mm....Adrian@
Could you supply one thats 6mm thick?

Adrian@

4,420 posts

299 months

Saturday 8th October 2011
quotequote all
Sorry, I only have the 10mm ones.
Adrian@