Rear wheel alignment 1990 300zx

nissan
300zx

#1

2 yrs ago had new tires installed and wheel alignment done. front was ok, but on back tires shop said were not fully adjustable and would have to do some fairly major work. so now after two summers of driving (5,000 miles), the back tires have half the tread gone. Has anyone else run into this issue and if so how was it corrected. at $140/tire, would like to minimize wear.THANKS


#2

You say ‘half worn’, but are they evenly worn, or show uneven wear across the tread? Uneven wear is a sign of bad alignment. If the rear cannot be aligned without ‘major work’, it’s up to you to determine if the work is worth it or frequent tire purchases is more feasible. Consider this: even if it has low miles, it is still a 24 year old car with, most likely, original rubber bushings, both in the suspension and in the sub-frame connectors. Rubber breaks down over time as well as through wear. Spending money on the suspension is to be expected on a car this old or older.


#3

Yes I had rear tire wear on my 86 Park Ave right off the car carrier. Alignment shop claimed the hold downs used could pull it out of alignment. Tire was almost octagon shape in no time. Four wheel alignment with the shim kits took care of the problem.


#4

2 thoughts:

First is that the alignment spec for the rear camber for a 1990 Nissan 300ZX is over 1°. That is NOT good for tire wear. It has to be under a degree if you want good tire wear. That means using a setting that is on the extreme or beyond it. Some alignment techs may not want to do that.

  • BUT -

The rear camber also helps give this car its great handling. So if you take camber out to get good tire wear, expect to lose some of what makes this car fun to drive.


#5

I second what @CapriRacer said. My MR2 is the same way - it’s set up for good cornering, which is bad for tires. If I let them, my tires would be bald on the inside half by the time the outside half got down to around 50% or so. I just take it to the tire shop halfway through the life of the tire and have them take the tires off the rims and swap them to the other side (you can’t rotate tires normally on original-wheeled MR2’s because the front and back wheels are different sizes).

I would suggest you might want to do the same thing. Costs around $30 unless the tire shop is in a good mood and gives it to me for free because I bought the tires there. No big deal.

Nice car, btw! I’ve always liked that generation of the Z.


#6

Describe major work to adjust camber? I had camber plates on prior car. Simple enough part. U could get 3-4deg additional camber.


#7

A lot of you guys are only talking about camber . . .

None of us has seen OP’s tires

How do we know it doesn’t actually have a toe problem?


#8

Maybe I’m just tired today but why wouldn’t you just leave the tires on the rims and move them to the other side? RR to LR, RF to LF? Or do you have to flip the tire around so that they are turning in the same direction?


#9

You have to keep the tires rolling in the same direction @Bing.

Some 300zx models had real wheel steering, I think it was the turbos. Now, that’s a complicated piece of machinery and I can imagine it could get pretty weird after 24 years. You should start searching for a mechanic who knows the way around these cars. A neighborhood shop is way over its head.


#10

I seem to recall many discussion about the rear alignment specs causing premature wear, as CapriRacer has suggested. I seem to also recall that Nissan had to change the alignment spec on these cars to address the issue, at the expense of some cornering prowess. A vehicle-specific forum might be an eye-opener.

However, you need to get that “major work”’ done first. Worn parts & bushing can only contribute to problems.


#11

thanks for the reply. the alignment shop said the adjusting bolts are seized to the sleeves, and needs both read upper control arms and lateral arms, and would also need to modify right front lower control arm mounting. I found all parts on Nissan parts warehouse website so will proceed soon