Backlash in a 2003 D90 Td5

[Blade74]

Hey all,

My car has a bit of backlash as sometimes when I'm on the accelerator and at the right acceleration it tends to backlash and its almost like the right resonance for it to to get worse and worse bouncing back and forth until I push the clutch in, back off harder or accelerate harder.
It's only got 47000kms on the speedo.

What would be the most obvious place that this would exists?
The front or back diff? The transfer case?
Or could it be possible I need a new clutch even though it seems ok?
I believe the front and back diffs in mine are both land rover and not Salisbury.
Cheers

[JDNSW]

The backlash is probably the sum of a lot of small amounts of backlash, with the major contributor being the centre diff - but I would carefully check to make sure none of it is in propeller shaft U-joints (unlikely) as you realy don't want to have one fail.

However, there is usually a fair amount of slack in Landrover drive trains, and it is usually not a problem. The effect you note is almost certainly due to the combination of the backlash and a dragging handbrake. The dragging can be confirmed by touching it (carefully) after a run or jacking up one rear wheel (chock other three) and turning the prop shaft (brake off, T/C neutral, centre diff unlocked) which should turn freely.

Drag will be caused by incorrect adjustment, sticking handbrake cable, or oil on the brake due to a leaking rear seal (this is the most likely).

Hope this helps,

John

[BilboBoggles]

I think the issue is more that you are getting surging when you are just about coasting. A defender can be smooth even with bags of backlash.

My MY03 has done this surging since new - 220,000 ks on it. I believe it's caused by the ECU map, as my MY03 has an EU3 map, and I've read that causes it to be more likely to surge. I've planned for many years to get a remap done for more power and drivability, but never got around to it. I don't really notice it now unless I try to make it happen.

[Blade74]

That might be it Bilbo,

I do have a stage 3 map in it.

I find that it is something that doesn't happen all the time and you can kind of make it happen by driving a certain way.
When it does happen I think it increase the effect of the back lash and over emphasis it.

I was just worried about getting off road on to rocky, bumpy, jerky terrain and having my car bounce backwards and forwards on the play in the drive train.

When you fit Ashcroft lockers do they work on your existing diff centre or do you put in a whole new diff centre? If you replace it what's the backlash like in the Ashcroft diff centre?

[goingbush]

Pry the plastic caps off your hub flanges, chock the wheels, put both main gearbox and transfer case in neutral / handbrake off , get under & turn the propshafts back & forth by hand, get someone to check how much the axle splines move in the drive flanges.

Any movement in the flanges is easily noticed at the gear change, You can get heavy duty drive flanges to help that,

Also you will find how much slop in the diffs, if the prop shaft rotates more than about 25mm then you need to get the diffs serviced, the front will have slightly more slop than the rear because the cv joints contain another small backlash.

to check centre diff backlash grab each propshaft and turn against each other, you may need to jack up a wheel to check properly.

other areas of backlash are transfer case intermediate shaft , Suspension rubbers & rear diff ball joint, as mentioned all these little bits add up.

I have replaced every one of these parts in my 110, the cheapest improvement was Drive Flanges, Replacing the Standard diff centers with Truetrac deleted most of the backlash, the propshaft only turn about 10mm now, Another cheap fix was trailing arm rubbers and rear ball joint. Then a steel sleeve & new intermediate shaft in the transfer case got the 110 almost clunk free, drives just like a car thru the gear changes now :)

[Blade74]

Thanks going bush,

So you went detroit truetrac over Ashcroft lockers.
How do you find them?
I do need to update my hole drivetrain.
Flanges, half shafts and diffs probably in that order.
Then later down the track my drive shafts. My car is standard height.
I really like the idea of the Ashcroft lockers.

[goingbush]

I decided on Truetrac over Difflocks because the Td5 110 has traction control, as would your 90 , Traction control and Torsen diffs are a match made in heaven , (Both Detroit Truetrac and Ashctoft ATB are Torsen LSD's) i considered that Fitting DiffLocks would be wasting the Traction Control,

I'm glad because they do work perfectly together and the strain on axles and cv's is much less, and also much less backlash than Diff Lock too. ( I had difflocks in my old 90) The operation is fully automatic and I don't need to decide to engage or disengage it, it just works and I'm oblivious to it, I hardly ever hear the Traction Control pump working, only downside is increased front tyre wear, by about 25%

Also Truetracs are very easy to fit into Rover diffs (not so easy into the salisbury)

here is a pic of the Truetrac next to my old rover diff centre, Its just swaps into place, its very easy to do as long as you know how to set the backlash & preload
https://www.aulro.com/afvb/images/imported/2013/08/477.jpg

special workshop equipment
https://www.aulro.com/afvb/images/imported/2013/08/478.jpg

cheers Don

[Blade74]

What's the difference between Ashcroft, Quaife and Detroit?

[Blade74]

So if I was doing the diffs I guess it would be best to do the half shafts and flanges at the same time.
Is Ashcroft the best option for all of the above?