The Stovebolt Site Forums The Shop Area General Truck Talk front end shake

i still have a occational front end shake on my 64 c20. it only happens when i am going 45 or 50, usually don't go much faster. i hit a pot hole or something and it starts the front end shaking that gets worse quickly till i slow down to 35 and it goes away. it has done that since i have drove it for 3 years or so. doesn't happen a lot but enough to be annoying. it has a new tie rod ends, ball joints are good, bearing adjustment is good. the only thing i can think of is it has a little wider tires on the front than stock- 31 x 10.5 x 16.5. anyone have any ideas what it can be. thanks

Bent wheel, belt separation in the tire, or perhaps a wheel weight got knocked off when you hit the pothole. Could also be loose lug nuts. I would suggest a trip to the tire shop to have the wheels/tires checked out. don't let them try to sell you an alignment, alignment will not cause a vibration.

Could be a loose shock or worn shock. Is it a up and down problem or do you feel it as a steering wobble in the steering wheel? A good steering stabilizer will control a lot of wobble in the steering linkage. Since it goes away when you slow down, I would suspect the whole steering assembly. Have you adjusted the steering box to remove all play and slop?

Your bigger tires will compound the problem due to the extra weight and rotating mass. Recheck the shocks or replace them with extra heavy duty ones, then move on to the steering box and all the joints.


Joe

I once had a similar problem on a 58' 1/2 ton. The spindle bolts and tie rod ends were in good shape. The shimmy would only show up after hitting a chug hole or some other type of bump.
I took it to a front end shop and they balanced the front wheels. I didn't think it would help but it did solve the problem. Funny thing is, there was no usual indication of an imbalance.
meansam

thank you all! it has had a alignment not long ago after the tie rod ends i replaced. not nuch play in the steering at all, i don't think it's that but might be. the front shocks is one thing i haven't replaced. i think i will do that next. i have been running these tires and wheels since i got it on the road. i will prob switch to a narrower tire on the front at least soon. hr

forgot to mention lug nuts are tight. i am going to try shocks first and maybe get 2 rims and some narrower tres for front, i can keep these 2 for spares. hr

I would suggest that you have the tires/wheels checked first before you put shocks on it. Shocks generally won't cause that kind of problem, as they only dampen the spring action. Most vibration/shake issues come from a rotating part.
Also, if you go to a narrower tire on the front, make sure you get a size that matches up well with the wheels, or get narrower wheels, too. Incorrect rim width to tire width can cause drivability issues too, such a severe wander and mushy cornering.

x2 on the shocks. I had that problem on my '62 Suburban. It'd shake at a certain MPH, and if I depressed the clutch, it went away. After checking everything else, I finally checked the shocks--when I pulled them out, I could completely compress them by hand and they didn't rebound! At all. Stayed that way until I took them to the scrap yard months later.

I've also had the issue come up again...not any particular speeds, and not bad, just a vibration. Tires were worn.
New tires, snugged the front wheel bearings up one slot on the castle nut, and lubed the front suspension. 900 miles to Floriduh the next day, and it honked down the highway at 90mph effortlessly. And smoothly.

-Brad

If everything has beeen checked for wear and is OK, I suggest you check the toe in. Front end shimmy is often due to a lack of enough toe in.

Uneven wear on the tire tread is a sign of worn shocks. Our school buses at work will show cupping of the front tire and when we check the shocks, they are loose as a goose! Joe

Alignment will not cause a vibration problem, exept by causing irregular tire wear.

A few years ago , I had a similar " shimmy " problem on my 1965 C10 . After a long elimination process , the problem was finally solved . It was a bad tire ( separated belt ) and once replaced , the problem was solved .

i think both shocks and tire/wheel check is what i am going to try. this truck has been doin' this occasionally for 3 years. the tires don't show uneven wear at all. anyone know what size of tire is recommended? this truck got a alignment just a couple of months ago after i replaced tie rod ends. toe in was set at that time so it should be ok. i didn't know but hoped the alignment would clear this up, but it didn't.
wow, 90 mph to fla, i'm impressed mine tops out around 55! i think narower tires on the front might help, they look awful wide. i would like to heep them on the back for towing since it's a wrecker. i should have changed the rear drums out to longer studs and run duallys. thanks for the ideas everyone. i am neck deep in my hudson right now so this shimmey will have to wait.

What width rims are you running? If the rims are too narrow, that will cause problems. I would suggest that you go to a 16" rim, then use a LT245/75/16 E load range, like what a modern 3/4 ton would use. That will give you plenty of load capacity, plus it will be a narrower tire. A 235/85/16 would also be a viable option, especially if you end up doing the duallie conversion.

I had the same problem for several years on 61 series 4000 with independent front suspension it had been to truck shops and tire shops for about 3 years and no one could find a problem, I had checked wheel run out tire out of round tie rod ends and toe in finally with it jacked up and prying just the right direction we found the lower ball joints were worn out, and it was hard to get it in the spot to find the wear for some reason, new joionts and it hasn't bothered me since.

believe it or not, and out of round REAR tire can also cause the front end to shake.
had it happen to me twice in the past, once on a 1970 mustang, and the other on my 2003 s-10.

leonard

JUST TIRED BLOOD.NEVER READ THE ABOVE .BALANCE THE TIRES,??RUNNING RADIALS CHECK FOR A BROAKEN BELT OR BALANCE THE TIRES.ALSO HAVE A NICE DAY.THE OVERSIZED TIRES WILL KILL THE WHEEL BEARGINGS CAUSING SHIMMY ON THE FRONT END.THE COOL LOOK OF THE BIG TIRES WILL CAUSE YOU MUCH HEART PROBLEMS IN THE LONG RUN

i wasn't running these just to look cool. i got them off a late 70's or early 80's 4x4 suburban. the rims look about 10" wide it's hard to tell for sure. the only size i can see on the tires is 31x10.5x16.5. i like the wider tires in the back for towing, but i think i would do for narrower ones in front. how wide are the stock rims suposed to be?

Hoggy, I just cured that same on my ford 450. The shimmy started a couple of years ago so I put on a new steering stabilizer and it went away. It was gone for over a year and then returned. At 45-50 it would go into violent front end shake and I'd hit the brakes and slow down and it was gone.
So I stopped by a front end shop and the chief wrench looks at it and says... I think you need new tires.
The tires still had good rubber so I went home and parked it and started on the wiring changes I needed for a new trailer.
A few weeks later I walk up to the truck and notice the left frt. looks weird. The darn tire had split open on the tread surface with ply separation.

The guy was right, two new front skins and problem is gone.
The hard part of this was replacing the tires when they looked good.

Dan

when the rear tires were out of round on my 1970 mustang, back in 1979, the local tire shop trued the rears up, while on my car, with a little lathe type machine that spun the tire, while shaving the high spots down, making the tire perfectly round.
that was in the old days.
cant find anyone around here that does that any more, so when i had a bad front end shake after getting new tires on my 2003 s-10, i jacked up the rear, with the tires just off the ground, spun the tires, and noticed one tire was out of round.
so i took the truck back to the place i had just bought the tires from, and they replaced that one tire, and it has been perfect since.
i had never thought an out of round rear tire could have caused the front to shake so much.

leonard

well, well, well- i finally got the problem solved! one of the tires was out of round on the front. thanks to all who responded. several of you hit the nail on the head and everyone had some good suggestions. i first took her in and had the tires balanced. didn't help a bit even though the tire shop said they were out. tried another place and they noticed one of the tires was out of round, but it didn't look like the tread was. i bought 2 new tires for the front to the tune of $300 for both. so looks like i now have the best of both worlds. the narrower tires are what i wanted all along, and the shimmey is gone. it steers with a little less effort in parking lots. it has always ran straight asa astring and the steering box has very little play, so it drives even better. thanks to everyone and i holp this may help someone else. hr