andyfreelandy
Well-Known Member
If only when turning right likely to be a front driveshaft, grab it and check for any free play. If when you turn either way then VCU may be getting tight.
Madmustang
Well-Known Member
Is it a Mk1 or Mk2 Freelander?
I thought Vcu initially was hoping it wasn’t but you have just confirmed it lol bugger is it a
It was the VCU unfortunately but fortunately have a very good friend who runs a great garage and got me sorted with a brand new one for a very reasonable price
No all four put on at same time Michelin does that make a big difference then
Good question - I never fully understood the logic.
Newer tyres on the front means larger rolling radius on the front wheels. This means the rear wheels turn more over the same distance so relatively faster, which because of the reduction gearing of the IRD (intended to turn the rear drive more slowly than the front) surely puts more pressure on the VCU?
Would be very happy if someone could explain why this isn't the case. It's late and my brain hurts
Personally however, as per the above, when replacing only 2 tyres I would put the new ones on the rear, not the front.
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GrumpyGel
Well-Known Member
The Freelander was designed to drive like a FWD but have AWD capability, as you say, the rear axle is under geared by a very small amount. If you then have less worn tyres on the rear this undergearing is then equalised (some) by the fact the rears want to turn slower anyway. With less worn tyres on the front, it will have the reverse effect and exaggerate this difference which will mean the VCU tightening will kick in earlier. That's how I take it.Good question - I never fully understood the logic.
Newer tyres on the front means larger rolling radius on the front wheels. This means the rear wheels turn more over the same distance so relatively faster, which because of the reduction gearing of the IRD (intended to turn the rear drive more slowly than the front) surely puts more pressure on the VCU?
Would be very happy if someone could explain why this isn't the case. It's late and my brain hurts
Personally however, as per the above, when replacing only 2 tyres I would put the new ones on the rear, not the front.
Nodge68
Well-Known Member
The rear is under-geared by comparison to the front. This means when 4 new identical are fitted, the rear propshaft is spinning slightly faster (by 0.8%) than the front. This slight difference in rotational speed is absorbed by the VCU, and it's designed to ignore it (It's in its slip allowance). However if new tyres are fitted to the front (larger circumference then the rear), then the gearing ratio changes, meaning the VCU has to slip more, which the starts to exceed the VCU slip allowance. Once the VCUs slip allowance is exceeded, it starts to transfer drive from the rear propshaft through the VCU to the front propshaft, which is why the IRD and rear diff take a real hammering.
So it's vital that 4 identical tyres (same make, same type) are fitted, and when 2 new are fitted, they MUST go on the back. This maintains the VCU slip allowance inside its designed slip window.
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Alibro
Well-Known Member
Has anyone ever asked a tyre shop to do this and if so what was the response? Any tyre fitter I ever spoke to hadn't a clue about it and would have said the new tyres should go on the front.
Nodge68
Well-Known Member
When I ordered 2 Yokohama Geolanders from Black Circles, I got a call from a chap saying that fitting 2 tyres to a Freelander wasn't recommend. I replied I know, the chap on the phone then he said "if I'm only fitting 2 to fit them to the back, or remove the propshafts".
As the propshafts were already off for my long turn MPG test, I told him it was now FWD, to which he replied, "OK I was just making sure you knew". In the 10 years I've had Freelanders, Black Circles were the only tyre seller's to mention it.
Alibro
Well-Known Member
kernowsvenski
Well-Known Member
I think that's pretty good of them. Fair play.
That's what I thought. Totally wrong to put them on the front.
