Any Suspension Gurus out there?

[Rockit]

Greetings, after a long absence, comes time to seek some advice from those more experienced than myself. Must say that I do peruse the site from time to time to keep informed. Anyway, my issue is this; For some time now, especially when travelling on a particularly smooth road surface, and more so at a slow speed, I have noticed a faint thump thump coming from the front part of the car On the rougher road surfaces it was not an issue. It is a great car, used on special occasions, had never done anything that I thought would flat spot a tyre. The car handled exceptionally well, and the issue never really bothered me. The front tyres on the car have done about 20k kms, are of Chinese origin, still have 2 or 3 mms left above the wear bars on them and have never given me doubt in their use. They are 225 40 18's, so a slightly lower profile than std.  Looking at the tyres through the wheel arch, I have often thought how well they have served and never noticed any abnormality. I do the servicing of the car, am under it - on my back, every 5k kms and have never noticed anything wrong - this episode makes me wonder. About 20k kms ago, I replaced the lower control arm bushes with Superpro ones, all seems ok there still. Following that, the alignment data worksheet seems to indicate that the measured settings were close to those listed on the G35 Service Data sheet. 

So, that is the setting, now to the present. The car did the near 2k km return trip to the Bathurst 12hr last weekend. Wasn't the fastest on the road, but it did some spirited driving  when conditions suited, like over Falls Creek. On the concrete section of the Hume, between Gundagai and Albury,  the thump thump became more prominent. A slight tendency to veer to the left also developed.

With the car home, thought it was now time for an investigation. Ha! still never doubted the tyres, took them off the car now up on blocks, and set them aside. Was overcast yesterday, a bit dark, getting late in the day, so I didn't bother getting too involved with looking for issues. Happened to move a tyre out of the way to do something else, that tyre being the worse of the two, and got a BIG shock.

I have seen tyres in the past that wear off on edges, but just can't understand how the wear pattern on these tyres originated. The acute wear section is inclined to be more down the side a bit, and on the better tyre of the two, the wear is smooth as though it has been seared with a hot flat surface. Yet then, in some smaller sections the wear is not a smooth flat surface, but looks like it has been scolloped out with a tool like that to get icecream out. The other tyre - wow! I should hang that one up as a momento.

There are known issues with these cars scrubbing out the inside of the fronts because of negative camber and there being no adjustment remedy. e.g. http://forums.redflagdeals.com/negative-camber-g35-559280/      That the car has 40's instead of 45's on it could also contribute. But accepting that, it seems to me that the tyres have been rubbing on something, yet there is no indication under the car that such has been happening. Rubbing on road surface?? I just can't get the angles to work

 

[GTSBoy]

Too much toe out.  Possibly just something (a bush) completely f**ked, allowing the wheels to flail around wherever they like when loaded in corners.  Might sit straight on a wheel aligner, but drive to toe out while moving forward or cornering.

[Rockit]

Thanks for the response. As a first step in getting this sorted, the car is booked in for  suspension inspection next Tuesday. Yeah, but it seems my problems don't end there. Down the right hand side of the pic with the most damaged tyre, there is evidence of a flat spot on the rim. Ha!, when I posted the pic, thought that it was just a camera illusion, but no, it's real. Have done a bit of research, watched some youtubes'; those that were repaired didn't come up 100%, and the general consensus seemed to be don't do it, - hmmm? Thinking a pipe bender with a couple of curved formers at either end??

So, by now there have been a few hrs spent searching the market for rims. That has included going back through the for sale section here for the last 12 months. Some 17's around, but not so 18's. I'm content with those that are on the car at present and don't necessarily want to upgrade.

Hello,,,,    anyone wanting to sell a pair of Rays 6 rectangular spoke OEM rims for a V35, mine are marked inside: Nissan Front,  18 x 8JJ / 30

I guess in that regard I would be grateful, just in case I have to go with a full set, to know why the rim would be marked "Front"? if anyone can wise me up please.  

[V35_Paul]

selling my V36 rims with tyres .

your Front rims are smaller

 

Edited February 12, 2019 by V35_Paul

[Rockit]

Will tie this one up. First, the damaged rim: ha!, repair it with a pipe bender? well that was a naive statement if ever there was one. Shane at Ace Alloys in Mordialloc, looked after me. The rim was in a bad way and distorted across the whole width, and the prognosis not good. He put it on a spinner and it appeared way out, I can't explain why I didn't detect it in the handling of the car? They have a press that doesn't use heat, and scored a winner, as did I. Spent more hrs researching, and the inbuilt negative camber in the car, and others, is recognized as a cause of premature tyre wear in the region that mine went.  Going down to 40's from 45's even aggravates this problem. I've stayed with the 40's because of vanity, but am trying Goodyear Directional 5's on the front. Will see what happens, but they can be swapped from wheel to wheel, so there is the potential to get wear from both sides of the tyre. Have Eagle Asymmetrics to go on the rear.  The car's suspension components tested out ok. Am now all but out of adjustment for the rear axle. The front toe ins were out, esp on the right side.