Nissan Patrol 4x4 (Africa)

My 2013 GRX recently had an ARB b/bar with T/max fitted. This necessitated a simultaneous suspension upgrade with OME. 20mm front and 30mm back (back right corner only still needs a trim packer - about 15mm down compared to left back).

Car drives beautifully with the new springs. Yesterday on the M1 north and round through to Centurion though I noticed that it has a steering wheel shudder when braking firmly at fairly high speed - say a true 120k/h (130km/h on the clock). Far less (hardly noticeable) at 80km/h and nothing at 60km/h. So that tells me that its probably not a warped disc.

I'm wondering if it could be that the castor is just about neutral and as one brakes it pushes it into positive (or maybe more positive) or possibly insufficient toe-in (hasn't been checked in 45k km since the car was new). I suppose that the only way to be sure is to have it checked with one of those Hunter alignment machines?

Any thoughts?

I doubt caster on it's own can cause a shudder, and suspect the problem is more likely related to tire wear or balance?

I would try rotating and seeing if that makes any difference.

Have you by any chance changed brake pads recently??

I had a very similar experience when I fitted 4.5 pads by accident instead of 4.8 pads.

Exactly as you describe your symptoms.

Peter Connan wrote: ↑28 Nov 2017 07:40 I doubt caster on it's own can cause a shudder, and suspect the problem is more likely related to tire wear or balance?

I would try rotating and seeing if that makes any difference.

Thank you Peter. I will check it out.

hugejp wrote: ↑28 Nov 2017 08:09 Have you by any chance changed brake pads recently??

I had a very similar experience when I fitted 4.5 pads by accident instead of 4.8 pads.

Exactly as you describe your symptoms.

Thank you JP. No, there has been no change of the brake pads.

To be honest, I think it might just be that particular road surface. I don't know why but only on the road between Johannesburg and Pretoria/Centurion do I sometimes get a bit of steering wheel shake. Yet I can drive a thousand kilometres from here to the Eastern Cape without experiencing it once.

I think I will just monitor the situation for a while longer and see what develops. It's not a safety issue, at least not yet.

Clem, when are we going to see a picture of this beast of yours with all its new hardware????

There's a picture of its *koff* in the checkstrap thread!

Will make a plsn!

Clem, looking at those photos of your Patrol in "barn door" post is like reading scope magazine in the old days, you can only see bits and pieces We want to see everything

.... Ian... you took the words right out of my mouth....

Get some brake cleaner in can spay the disks and try again it sorted my problem out