Thread: Need diagnostic help on SEVERE steering wheel shake

Tweet

A guy I worked with bought something like an 08 Jeep and it had DW. He took it to a 4 x 4 shop and it turned out the dampener was worn out. Replaced it and it went away. So you are right about the importance of one. Don't know if one can be added to a MMII front end, but they sure don't hurt.

Don

Take and put the wheels and tires off of something different and drive it and see if it goes away. I bet that the steel belt in one of the tires is seperating as the wheel spins. When you stop, it returns to normal and then starts up again after a touch. It will be a violent shake. A seperated belt doesn't always stay as a swollen up knot on the tread. I beleive you have a bad tire. I even had it on a balancer and it spun good. It would only do it on the car with the weight on it. ( Went thru this crap on my wifes car ) I learned something on that one.

Originally Posted by Weasel Diesel

Take and put the wheels and tires off of something different and drive it and see if it goes away. I bet that the steel belt in one of the tires is seperating as the wheel spins. When you stop, it returns to normal and then starts up again after a touch. It will be a violent shake. A seperated belt doesn't always stay as a swollen up knot on the tread. I beleive you have a bad tire. I even had it on a balancer and it spun good. It would only do it on the car with the weight on it. ( Went thru this crap on my wifes car ) I learned something on that one.

Changed tires now to 3 different combinations, same symptoms, though slightly better (less violent) the larger the tire I used. Two of the sets were 2010 dated tires (the larger ones) the small sets were a real miss-match (2007 & 2009 dated).

BT---

scrub radius-----take a line thru the upper and lower ball joint and it should pass thru the center of the tire/pavement contact patch--

I once had a car that the wheels/balance weights hit the brake components.

Did you measure/examine the brake rotors???

It seems you are wondering around in circles and not eliminating possible causes--

does the wobble worsen/lessen with more /less brake pressure???

What are the results of the alignment??? actuall numbers for toe, caster, camber left and right---

How much did you lower the car???
I am assuming the car in your gallery is yours?

The "55 mph" and "Goes straight" part sorta sounds like a driveshaft out of phase or out of balance.

Death wobble is a common demon on Jeeps with 33" and larger tires running on the highway. While it can be a real bear to solve, it almost always involves some combination of caster and/or toe in out of spec plus one or more worn components in the front end, either tie rod ends, drag link ends, pitman arm, ball joints or panhard bar. One of the biggest causes is the panhard bar mount being loose, or having worn ends allowing the differential to oscilate side to side on up and down suspension motion. I understand that the panhard bar is not a possibility here on a MII IFS - just pointing out that it is a common demon on 4WD's.
The steering dampner by itself is not going to solve death wobble - it is indeed an important component, especially with big, aggressive off-road tires, but if you have things out of spec the steering dampner is a temporary band-aid at best. IMO you need to be looking for a worn front end component, plus being sure your caster and toe are set on the money.

Originally Posted by jerry clayton

BT---

scrub radius-----take a line thru the upper and lower ball joint and it should pass thru the center of the tire/pavement contact patch--

Thanks!

Originally Posted by jerry clayton

once had a car that the wheels/balance weights hit the brake components.

Checked, not happening

Originally Posted by jerry clayton

you measure/examine the brake rotors???

on my list to do next

Originally Posted by jerry clayton

the wobble worsen/lessen with more /less brake pressure???

lessens with more brake pressure

Originally Posted by jerry clayton

are the results of the alignment??? actuall numbers for toe, caster, camber left and right---

Front Left / Right
Camber -1.4/ -0.7
Caster 1.6 / 2.5
Toe 0.12 /0.11
SAI (?) 9.3 / 10.1
Included Angle 7.9 /9.4
Cross camber -0.7
Cross castor -0.9
Cross SAI -0.7
Total Toe 0.23

Rear Left/Right
Camber 0.1 /0.0
Toe -0.01/ -0.15
Cross Camber 0.1
Total Toe -0.16
thrust angle 0.07

Originally Posted by jerry clayton

much did you lower the car???

4" front, 2" rear (not certain what stock levels were, this is from "pre-change" numbers)

Originally Posted by jerry clayton

am assuming the car in your gallery is yours?

yes...

Originally Posted by jerry clayton

seems you are wondering around in circles and not eliminating possible causes--

Completed many of the the suggestions, but have compiled quite of list of where else to look which will wait until next weekend (work days) wheels off today to be rebalanced at a specialty alignment shop today. Will check the rotors with a borrowed cal tonight.

Couple things---

If it gets better with more brake---that is the result of getting the disc squeesed down to same distance as it goes around.

Is this a front end that was removed from a mustang2 and installed or is it an aftermarket--Heights, etc?

whoever did the front end alignment didn't care or know what he was doing--sure those numbers are in spec acording to there specs but there isn't any of them where they need to be and also the same on both sides.

does the upper control arm mounting have any brake anti dive angle in it???

Originally Posted by jerry clayton

Couple things---

If it gets better with more brake---that is the result of getting the disc squeesed down to same distance as it goes around.

Is this a front end that was removed from a mustang2 and installed or is it an aftermarket--Heights, etc?

removed from a M2 & installed by PO...

Originally Posted by jerry clayton

did the front end alignment didn't care or know what he was doing--sure those numbers are in spec acording to there specs but there isn't any of them where they need to be and also the same on both sides.

Tell me about it, when I questioned the wide differences in number on each side, he reassured me that as long as it was "in range" it's fine and that if I was still having a shake, it was probably something else, other than the alignment. Was done at a Tire Kingdom... I'l try to get the car to a rod shop as soon as I check a few more items for a new alignment..

Originally Posted by jerry clayton

the upper control arm mounting have any brake anti dive angle in it???

pardon my ignorance, but I don't know what "brake anti dive angle" is or how to determine. thanks!

Bart

BT

Go to www.heidts.com

Pull up there online catologue and print/read pages 4-12-----

Explains a lot about mustang 2 front ends and proper set up including drawings that explain some different terms----

You will be a lot smarter by twilight tonight!!!!!!

Jerry

have you had the car on a alinement rack yet???check all the frame dim. dtd a profressional install the front clip???a lot of time you need an old timer to adjust the front end because they know how to adjust with out a computer.ask your friends who's the best front end guy in your area and go see him.

Originally Posted by hotrodstude

have you had the car on a alinement rack yet???check all the frame dim. dtd a profressional install the front clip???a lot of time you need an old timer to adjust the front end because they know how to adjust with out a computer.ask your friends who's the best front end guy in your area and go see him.

scheduled 8am tuesday, June 15th Weber Wheel in WPB, Fl.... "old school" shop/owner...

I think that is an excellent question hotrodstude raises about how competently the front end might have been installed. Although building a rod has gotten easier in recent years because of all the kits out there, it still isn't a no brainer and the job can still be botched. We have all seen examples of poor workmanship, sometimes even done by "professional shops".

It's a little surprising to see this problem, which to me sounds like classic death wobble, evident in an independent front suspended car. I always associated that problem to the cars we straight axle guys owned. After all, some of the reasons guys install these MMII kits is to get better ride, handling, and none of the quirky steering issues the straight axle cars are blamed for having.

Since you bought a car that someone else built I think you need to go back to square one and make sure the axles are square to the frame, that the wheelbase is the same side to side, that the front suspension was installed in a proper manner, etc, etc. There are too many unknowns here and this problem could be the tip of the iceberg. Maybe time to get a GOOD rod shop to take a hard look at it and offer some opinions and solutions. Your local alignment shop is out of their element on a custom built car in most cases.

Don

Originally Posted by Itoldyouso

I think that is an excellent question hotrodstude raises about how competently the front end might have been installed. Although building a rod has gotten easier in recent years because of all the kits out there, it still isn't a no brainer and the job can still be botched. We have all seen examples of poor workmanship, sometimes even done by "professional shops".

It's a little surprising to see this problem, which to me sounds like classic death wobble, evident in an independent front suspended car. I always associated that problem to the cars we straight axle guys owned. After all, some of the reasons guys install these MMII kits is to get better ride, handling, and none of the quirky steering issues the straight axle cars are blamed for having.

Since you bought a car that someone else built I think you need to go back to square one and make sure the axles are square to the frame, that the wheelbase is the same side to side, that the front suspension was installed in a proper manner, etc, etc. There are too many unknowns here and this problem could be the tip of the iceberg. Maybe time to get a GOOD rod shop to take a hard look at it and offer some opinions and solutions. Your local alignment shop is out of their element on a custom built car in most cases.

Don

All good points, if the trip to Weber doesn't solve it, I'll see if I can find a respected shop in the area. Only one I know of in this area is "Rick's Rods" in West Palm Beach, but have heard mixed reviews.

Could you have switched these from side to side? Without strut rods it would be easier to mix up.