Slight front end shimmy @ 52 mph any ideas?

[gubba]

Hey gang..well I have another question for you all. I just finished the switch over from generator to alternator and found a tr7 fan blade to install on my 1963 tr3b. As I had some other front end issues I wanted to attack I went threw the front end. As I always had a shimmy at 52mph I replaced the sterring nuckel ( it was worn out) and put new grease boots on everywhere and checked all the ball joints all is good. Okay went for a test drive..nothing fell off or blew up and the shimmy was much less but still there. Any ideas? I am running whire wheels with nockoffs.

 

[Mickey Richaud]

Swap the tires front to rear (one at a time) and see if anything changes. If so, probably a tire/wheel issue.

 

[NutmegCT]

One thing to check (among others) -

Put the car on a lift, or, one at a time, raise each wheel off the ground. Spin the wheel and see if the high part of the wheel "wobbles" in and out (left and right when you face the front of the car). A bent wheel can cause a wobble at a certain speed, then seem to smooth out above and below that speed.

I had a "45-55mph wobble", even tho' the wheels had new lead weights from a spin balancer test. I braced my arm and held a pencil pointing toward the side of the tire. Spun the wheel, and saw the rubber (and the wheel itself) move toward and away from the pencil point. Not good. Found out I had 3 bent wheels. Got new wheels - problem solved. Probably happened over many years of owners hitting chuck holes, curbs, etc.

It's not a bent *lip* of a rim - it's an actual bend in the center of the wheel itself at the hub that causes the problem. Most times it can't be straightened without weakening the steel.

Tom

Edit: Oops - I'm describing my steel wheels - not wires.

 

[TR3driver]

It's not a bent *lip* of a rim - it's an actual bend in the center of the wheel itself at the hub that causes the problem. Most times it can't be straightened without weakening the steel.

I'll disagree, when they are wire wheels. A wire wheels needs to be 'tuned' occasionally throughout its lifetime, which includes making sure the rim runs true to the hub. Far from weakening them, proper tuning actually makes the wheels stronger because it ensures that the spokes share the load evenly and don't get shocked when a loose spoke suddenly becomes tight at each revolution.

https://www.mgaguru.com/mgtech/wheels/wl109.htm

 

[Brooklands]

On my 3B, when the previous owner switched to a Rack and Pinion steering box, he mounted it on a bracket of his own design, and then bent the steering column and tie rods to match. The steering box was remounted in the proper position and that seems to have fixed things on my shimmy around 50 or 55 (still have not gotten the speedometer corrected so I use the tach to approximate speed). We also went through the five wheels, found the best four and mounted new tires and put the best old tire on the spare. Spokes were tightened as needed and everything seems pretty good now. I had expected the wheels to be the whole problem until we found the butchered update by Pedro's friend who had owned my car previously... :laugh:

 

[TR3driver]

Not that it's necessarily relevant; but I recall many years ago my Dad bought a Chevy wagon that had a fairly serious shimmy only at a specific speed. He thought at first it was tires, so installed carefully balanced new ones, but the shimmy remained. Then he changed the shocks & ball joints, same story. At higher and lower speeds it was OK, so he just avoided driving the wrong speed.

Then a few years later, the tires were replaced again (first new set wore out). The shimmy disappeared! Apparently, it had been ball joints, etc.; but the tires had taken a set so the problem actually switched from being suspension to being tires!

I also had a severe shimmy in my motorhome, that happened only sometimes at certain speeds. Believe it or not, a friend of mine (who ran a tire shop) solved the problem by doing a static balance on the front wheels, instead of dynamic balance. It never happened again.

 

[prb51]

When I got my TR3 I had shimmy and major scuttle shake so:
Found out the steel wheels could not be properly balanced (out of whack seriously) replaced with new dayton 60 spoke wires.
This reduced the major scuttle shake..still shimmy
Rebuilt the front end completely, all rubber to poly, all new ends/bushes etc.
This reduced the scuttle shake to one RPM range as you have
Replaced the steering box w/new Rack and Pinion
No shimmy, steers w/ one finger, tracks true.

Between the front end wheel/rubber bushings/ multiple tie rod ends/ silent block bushes etc. and finally play in the steering box there are numerous places for slack to allow shimmy. Locating it can be just about luck without an all out look about.

 

[NickMorgan]

There seem to be three common reasons for wheel shimmy at around that speed.
The usual suspect is wheel balance.
The next is incorrect wheel alignment.
The third is one or more wheels out of true.
I have had four bent steel wheels in three TRs and these have been the cause of the shimmy each time.

 

[martx-5]

... Believe it or not, a friend of mine (who ran a tire shop) solved the problem by doing a static balance on the front wheels, instead of dynamic balance. It never happened again.

Living on Long Island all my life, back in the '60s I used to frequent Bridgehampton race track. Everything was always laid back, and you could always wander around the pits. I can still rememeber watching the Goodyear tire guy installing new rubber of the racers and using a <span style="font-weight: bold">static</span> balancer. Seemed to work just fine for all those race cars. I used to own one, but in one of my house moves it got lost.

 

[NutmegCT]

It's not a bent *lip* of a rim - it's an actual bend in the center of the wheel itself at the hub that causes the problem. Most times it can't be straightened without weakening the steel.

I'll disagree, when they are wire wheels.

...

Thanks Randall. I was describing my experience with steel wheels (not wires) but forgot to say so. Sorry 'bout that.

Tom

 

[prb51]

My steel wheels were/are warped in the lug nut area....no way to fix without spending way to much money...if it can be done at all safely

 

[TR3driver]

Nope, for steel wheels I agree entirely with Tom. Even if you can find someone that agrees to try, don't do it. They are weak and known to crack in the center section anyway; trying to straighten them is just asking for trouble IMO.

Which is a shame, because I've got a couple of nice looking wheels that are bent in the center.

 

[GilsTR]

After fighting the "Shimmy-Shimmy-Co-Co-Puff" for way too long
found it was my wire wheels. Had them "trued" several times.
Hung tight...and found a good sale on TRF and BINGO...
Shimmy all gone! Gil

 

[pjsmetana]

I find it strange that no one mentioned that he should check his alignment... granted the problem usually gets worse with higher speed, but depending on your wheels, tires, and the road, thats not always the case.

EDIT;

The next is incorrect wheel alignment.

So never mind me haha!