Anyone have an experience/expertise on rim runout? I've been chasing a vibration on my XJ for several years now. Been through multiple sets of tires, road force balances, been to 2 different rim shops, measured runout on my own, etc etc. I'm tired of chasing this and getting bad info from "pro" shops. Everything on the suspension is fine, bushings have been replaced. I'm fairly sure it's tire related because rotating tires front to back does change the vibration I feel in the steering wheel.

I realize the only way to really check the rim runout is to dismount the tires and measure at the inside beads. Barring that, do measurements at the face of the rim have any meaningful value? I'm talking about 0.050" not a rim that's been bent over 45 degrees. If I measure radial and lateral runout at the inside edge, I get within 0.015".

Is it worth trying to find a shop that can do a vibration analysis and pinpoint which corner or if it's wheel/drivetrain vibration before I go any further? I'm thinking the only other thing I can do is buy a reconditioned rim, measure it, and swap one tire to have a known good. Doesn't help, though, if I have more than 1 bent rim.

Any advice/thoughts appreciated.

Michael

 

MIchael, I would try rotating the tires front to rear only on 1 side of the car. If the vibration changes, then you know the rear tire on the side that you just swapped is aiding to the problem. If things remain constant, then swap the other side only. See if the vibes change then.

As for run out on the inside or outside of the rim I don't think really makes any different as long as you don't have road rash on the rim itself. If you only have 0.015" of wobble in the rim, then that should not cause any wobble. So, not sure what to say other than making sure that your rims fit tight to the center bore. I could possibly see where you would get some nasty wobble if your rim didn't sit flat against the hub or could move slightly. Granted, I would think any movement would result in wear on the rim. Speaking of something on the hub, you may have a crumb of something on the back side of a rim which is causing it to not sit square to the hub. Would be atleast worth a look.

 

Michael,
re-reading your post you say there was a noticeable change when rotating the wheels front/back so then it can't be rims or tires, given you've tried different tires,
Q?'s what year is your model & what speed does this happen, i've had something similar , i have wire rims & confirmed the balance is right, what i found was the steering rack needed a slight adjustment and the tie rod arms needed spring replacement mainly one side as it was compressing to easily under pressure, you can also have the wheels balanced on the car, did this many times in my mechanic days, this will eliminate wheel & rim balance being the problem, if all balance well & still have steering wheel shimmy - then you'd be looking at steering rack, if steering has no wobble & still a vibration then you have a drive line problem .... a badly bent rim will be obvious to the eye, the slightest rim run-out is absorbed by the tires.....don't get too fixated on on thing, go with the basics as i've suggested.

 

Can you explain where the springs are on a tie rod end?
I have not heard of this before?
Do you have a pictures as I maybe not understanding?
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When I worked at the dealer we were required to have a 'ROAD FORCE' type balancer.

The machine was sensitive enough that it would tell you what tire to put on which wheel as well as the orientation.

It could take hours to measure/spin each wheel and each tire to get the optimum settings.

 

It's a 2006 XJ8. The vibration feels bad at most all speeds over 30 mph. I've been doing some more driving and realize I have 3 distinct feelings in the steering wheel:
1. Tire/wheel vibration, most prevalent at highway speeds
2. Road feel - the actual texture of the road, all speeds (tires are only 2 years old)
3. Driveline vibration - slight, can feel the difference between on/off load.

I've driven the car back/back with a late model Chevy, really apparent how badly the Jag relays the road texture through the steering wheel, while going over same roads.

In the past, I have always had 1 "bad" wheel assembly that would make more vibration on the front, got better when moved to rear. Did NOT matter how many times I got new tires or balances. Now I suspect I have 2 bent rims so there is no way to hide it with rotation. I've gone ahead and ordered a reconditioned rim. I will measure the new rim to ensure it's within spec. Then I will swap with one of the suspect wheels, so I have a known good. Then I can check the old rim and see if it had appreciable runout.

I had a rim shop tell me my rear rim was bent, but when I spin it I see nothing obvious. I spin my front rim by hand and can see lateral runout. They said this one was fine. When I measure I'm looking at +50 thousandths on the front, +25 and -35 thou on the rear. No really good way for me to check radial runout with the tire in place.

 

so how did you get bent rims? go through a big pot hole you haven't mentioned tire pressure, what do you have all tires set to?, no mention wheel alignment & steering rack adjustments or testing?

 

It's hard to say how they get bent but it has to be from impacts?
When I traded my rims in from my old 2005 STR they told me 3 out of the 4 were bent and I had to pay extra so they could repaired and used as trade ins. But my car drove fine and I had no problems?
So I wondered if they tend to get bent over time rather than from one big impact? Just guessing here.

I will say on my current Jaguar I have factory forged rims and have become a BIG believer! Several years of use and major pot hole impacts with zero damage so far!
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The left front rim got hit in an accident. The other rim I suspect is bent since before I got the car.

I purposely left out that bit of information, because I feel that it's too easy to jump to conclusions about other things being broken. I just wanted to know what runout specs were considered acceptable and measurements made from the face of the rim. I'm very familiar with how to check tie rods, suspension arms, bushings, ball joints, etc etc, and I have checked everything thoroughly on the car. The alignment is not out, bushings are not bad, tires and pressures are all perfect (30/32 psi front/rear).

Case in point-- 2 weeks ago I took the car to a rim shop, told them about the accident, that the front rim was hit, and I suspect it's bent. Also asked them to check the left rear. They come back with "your front rim is fine, your hub is bent." Of course that's BS, if I had a bent front hub my brakes would be vibrating like crazy. But I went back home, took it all apart, and measured 0.000" of runout in the hub face. So it was a big waste of time.

 

your tire pressure will give a softer road ride but will increase the road noise also reduce the life of the tire, i've always run tires @ least 36 psi, less noise - easier on the steering & last longer. i have no doubt you are ok at checking front end etc, we don't know that till we suggest it, i was suggesting the steering rack ends not the tie rods - if not withing specs the spring loaded joint will be weak & cause a wobble............anyway i'm sure you'll get to the cause eventually, just a bit difficult for us to help as we're not there to see it.......

 

I can certainly increase the tire pressures and see if that makes any difference to the road feel. That's easy enough to check.

No offence intended, I do appreciate everyone's feedback. I also certainly understand how difficult it is to diagnose remotely. Since the rims are suspect I will focus on those, should have my new (reconditioned) replacement today and will report back what I find with that.

 

Well... that was an expensive way to learn something. The rim shop swore my left rear rim was bent. Got the new (refurbished) one, measured it, everything well within 15 thou. I had it swapped for the old one. Measured the old rim, it isn't out even 10 thou. Not a damn thing wrong with it.

I did notice something, and the tire guy independently confirmed, my tires all have flat spots. The car doesn't sit more than few days without moving, and I had just driven it several miles so the flat should have been worked out. Conti PureContact that are less than 2 years old, about 7000 miles.

 

Quick update:

With the new rim on the front left, the steering wheel vibration has completely gone away. I could not be happier with the smoothness of the ride at all speeds. There is a little bit of road feel, but it's not obtrusive.

With the new rim on the front left, I put the rim that was hit on the rear left. Since I had confirmed my previous rear rim was within spec, I had that swapped over to remove the rim that was suspect and had cosmetic damage. Two things:
1. The rim that was hit is perfect within spec. Damage is cosmetic only.
2. The tire that was moved to the new rim took noticeably more weight to balance. My other 3 wheels have 3/4-1 oz weights stuck on, nothing clipped to the inside edge. This tire that was just moved to the undamaged rim has a double row + a weight on the inside lip. I am wondering now if this has been a tire problem all along. Have only driven up to 55 mph, and it's smooth, so l have no complaints. But it's something for me to keep an eye on if I rotate this tire to the front and the vibration comes back.

Something else that may be contributing, the tire shop left the pressure at 36 psi and I hadn't adjusted down. xjtom, you had mentioned running higher pressures than the sticker indicated. I'm now wondering if this is a necessity for me to avoid the flat spots. I'll give it a try at 33/34 psi all around and see how it does. Adjusting tire pressures is the easy variable to play with.

 

Something that poeple do not realize is that a rim is off balance because of the hole for the stem and that tires are manufactured to account for this. So, if the mark on the tire is not lined up with the valve stem, you can end up with a lot of weights to balance the tire. How each manufacturer marks the tire differs. But, a lot of times, it is just a dot on the tire. I would see if in your case the two match up. It is an easy thing to overlook. From my experience, a good tire shop will rotate the tire some to help minimize the need for weights. But, this still normally keeps the dot near the valve stem.