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Death wobble seems to be gone.

donsrods

Member
I thought I would give an update on a problem we were having with my Son's T bucket, it had violent death wobble when you accelerated and the only way to stop it was to stomp on the brakes. Part of the problem was we rushed building the car, we did it in 88 days, start to finish because we were shooting to have it done for Turkey Run last Thanksgiving weekend. That was a complete build up, including building a new frame from scratch.

Finally we decided to just go back to square one and redo all the alignments, rebalance the wheels, and get the heavy GM brakes off of the front end. We found a lot of things wrong, like the wheelbase was 9/16 off side to side, the toe in was 3/16, the caster was too much at 11 degrees, the tires were out of balance and one brand new rim was bent right out of the box. I also adjusted the Flaming River steering box to take up some slop, and realigned his pinion angle. We also cranked down his friction shocks a lot tighter.

He hasn't driven the car since November mainly because of the handling issues, but also because his brand new TCI streetfighter transmission went out. TCI sent us a new one and new torque converter, and we finally got that installed a few weeks ago.

To make a long story shorter, he has been using the car a lot in the last few weeks and it goes right down the road now. :D Just last night we took our two cars to a cruise and he can now get on it hard and it never had one problem. He can one hand it going down the road, and it doesn't wander like it had been doing.

I think the biggest thing that helped was getting the heavy GM brakes off of the front end and putting much lighter Wilwood brakes on it. We also replaced the spindles with brand new ones, and found one of the old spindles was turned 5 thousandths too far, allowing the outer wheel bearing to be sloppy. I thought I would tell anyone who is having a similar problem that it is curable, you just have to keep playing with the car and make sure everything is set up correctly.

Don
 
You are right , once you have it happen you NEVER want it to happen again. :eek:

My T also developed death wobble after driving it for about 1000 miles. I had the front wheels checked and one was slightly bent, plus my shocks were too weak. I just put two new shocks on and it really made a difference, now I just have to paint and install a new wheel to fix it 100 percent.

Don
 
donsrods said:
I think the biggest thing that helped was getting the heavy GM brakes off of the front end and putting much lighter Wilwood brakes on it. We also replaced the spindles with brand new ones, and found one of the old spindles was turned 5 thousandths too far, allowing the outer wheel bearing to be sloppy. I thought I would tell anyone who is having a similar problem that it is curable, you just have to keep playing with the car and make sure everything is set up correctly.

Don

I have the GM brakes on my T and I haven't had any problems with them.

There is an excellent article written by Tim "Toolman" Taylor (yes that's his real name) on how to square up your chassis over on the Tech Pages of the NTBA site. NTBA
We did this to my T-bucket and it now drives like a dream.
 
donsrods said:
I thought I would give an update on a problem we were having with my Son's T bucket, it had violent death wobble when you accelerated and the only way to stop it was to stomp on the brakes. Part of the problem was we rushed building the car, we did it in 88 days, start to finish because we were shooting to have it done for Turkey Run last Thanksgiving weekend. That was a complete build up, including building a new frame from scratch.

Finally we decided to just go back to square one and redo all the alignments, rebalance the wheels, and get the heavy GM brakes off of the front end. We found a lot of things wrong, like the wheelbase was 9/16 off side to side, the toe in was 3/16, the caster was too much at 11 degrees, the tires were out of balance and one brand new rim was bent right out of the box. I also adjusted the Flaming River steering box to take up some slop, and realigned his pinion angle. We also cranked down his friction shocks a lot tighter.

He hasn't driven the car since November mainly because of the handling issues, but also because his brand new TCI streetfighter transmission went out. TCI sent us a new one and new torque converter, and we finally got that installed a few weeks ago.

To make a long story shorter, he has been using the car a lot in the last few weeks and it goes right down the road now. :lol: Just last night we took our two cars to a cruise and he can now get on it hard and it never had one problem. He can one hand it going down the road, and it doesn't wander like it had been doing.

I think the biggest thing that helped was getting the heavy GM brakes off of the front end and putting much lighter Wilwood brakes on it. We also replaced the spindles with brand new ones, and found one of the old spindles was turned 5 thousandths too far, allowing the outer wheel bearing to be sloppy. I thought I would tell anyone who is having a similar problem that it is curable, you just have to keep playing with the car and make sure everything is set up correctly.

Don
I hope you found a pitman arm since you wont return any of my emails or phone messages. I thought you fell off the planet. Glad to know you and your son are o.k. Mikey
 
Mikey, I had a major computer crash, lost everything in it including pictures and all the sites I used to visit. Even my email was wiped out totally. I've been putting back stuff into the computer as I come across it. Glad to see you are here, and yes, Dan found an arm locally, but thanks for asking.

Oh, and I also washed my phone with a load of clothes, and had to get a new one with a new number!!

Don
 
I was interested in this thread because I am just digging into an old T frame and bucket project. My front axle originally had about a 10 1/2" disc and Airheart calipers, but these were left sitting in the mud, and broke apart on removal (bolts rusted/broken, aluminum caliper corner broken off previously). I was thinking of going with the GM conversion with "factory" type mags off a Ranger pickup but read the warnings about the extra weight. Anyone know just how much weight we are talking about here? Any others had good luck with this conversion? I am leaning toward a 4 cylinder - maybe even a little diesel 4 banger, so the front end will not be as heavy as some of the V-8s are. Thanks in advance for any input. Jim
 
I am using '74 Nova rotors and calipers on my car with absolutely NO problems. There are several other T's in my area with similar set ups and they are not experiencing any negative results either. Perhaps we are just lucky but I rather doubt it.
 
I thought of another option. If I were to use the adapters to GM calipers, is there a way to adapt the GM caliper to my .32" rotors? That is, is there a "spacer" that can go behind the pads, or maybe a thicker pad available? I realize that this would "waste" the outside half inch of the pads, since the GM rotors are 11" and mine are 10 1/2", but I think that it would still give me more stopping power than the original Airhearts, AND less weight than the GM rotors. Any thoughts or leads on the spacers? Thanks, Jim
 
I know that there are a lot of guys running the GM discs on the front of straight axle rods with good results, and to be honest, I don't know how much, if any, they were contributing to the problem. As I mentioned, we did about 10 other things to the car at the same time, so it could be a combination of all those little problems that added up to one big problem.

As I also mentioned, Mickey from Total Performance told us we would not like the GM discs. Since he has been in this business for the past 30 or more years, I would guess he has formed that opinion from observations. All I know is that we were not going to take any chances with my Son's safety, so we did everything we could think of to correct the problem, including pulling a brand new set of GM discs off and going to Wilwoods.

Whatever we did evidently worked, the car now tracks straight and even when he punches it hard, no more death wobble at any speed. Just last night my two Son's and I took both T's out for a little cruise and we both were able to get into the carbs a little with no handling issues. Obviously, I am pretty relieved and happy about that. :)

I suspect that the set we had also caused the previous owner problems, because he pulled them off of his customers car to install Wilwoods. I bought them on Ebay, and they were nicely chromed and complete. We did put new rotors and bearings on them just to be safe, but after we started having problems we kind of understood why the other guy got rid of them.

To be honest, I'm not a fan of discs on the front of hot rods anyway, mainly because they are dirty as h***. The drum brakes I run on my other cars run clean, but the GM discs and the Wilwoods put off a tremendous amount of brake dust that forces Don to pull his front wheels often for cleaning. I know I'm old fashioned, but that is just the way I see it.

Don
 
Don, you're not kidding about the brake dust. I always need to clean my wires after a good weekend of driving, but this being my first hot rod, I'm taking it in stride. I'm also glad my wires are black. I bet the guys running chrome wires dread the task of cleaning that dust off.
 
Try ceramic pads they shouldn't give the black dust.The best quality ones are really hard so they don't produce dust. Some rotors do have problems with pads that aren't ceramic most new cars require them.
 
That's called priorities Al. Important things come first. I'd be willing to bet if you had built your truck from the ground up, you'd feel different about washing it.

Ron
 
If you have GM calipers, the Bendix Ceramic pads are the best for keeping the dust at a minimum. I know they are spendy, but they are well worth it
 
I know this is an old thread but I just experienced the "death wobble" have 2000 miles on the chassis and will be going back to check everything, one thing I noticed about my GM front discs other than they are butt ugly is they have a hardened pad, dust is minimal but they squeek like a mofo.
Another thing, after seeing what the death wobble is with wheels flopping back and forth, makes me think that one should assume the alignment was thrown out for sure. I'll start with checking squareness of front and rear axle with the frame, alignment. wheel bearings heims and right down to the shocks and wheel runout and tire balance. I ordered a SoCal steering dampner too.
 
I was interested in this thread because I am just digging into an old T frame and bucket project. My front axle originally had about a 10 1/2" disc and Airheart calipers, but these were left sitting in the mud, and broke apart on removal (bolts rusted/broken, aluminum caliper corner broken off previously). I was thinking of going with the GM conversion with "factory" type mags off a Ranger pickup but read the warnings about the extra weight. Anyone know just how much weight we are talking about here? Any others had good luck with this conversion? I am leaning toward a 4 cylinder - maybe even a little diesel 4 banger, so the front end will not be as heavy as some of the V-8s are. Thanks in advance for any input. Jim
The 4 cyl. cummins diesel weighs roughly what a BBC weighs.
Just got thru about 6 months ago building a Ford 2.3, Paxton blower with dual Weber sidedrafts, mean little motors....
 
If you go 4 cyl. diesel, go with some of the Tractor motors like Kubota and the like, they're lighter....or look into a motor off a reefer or some small piece of industrial equipment....Hopup potential is way on up there....
 
The 4 cyl. cummins diesel weighs roughly what a BBC weighs.
Just got thru about 6 months ago building a Ford 2.3, Paxton blower with dual Weber sidedrafts, mean little motors....
Whoeee, one of Mr Esslinger's fine Ford Pinto clones with turbo to make an easy 500hp and around 400lb weight would be an awesome bucket engine. And virtually indestructable, which is why they are so popular as a Midget powerplant. 6 speed Hollinger stick and C16 in the tank, go out looking for unsuspecting V8's on Friday cruise nite. :)
 
Try ceramic pads they shouldn't give the black dust.The best quality ones are really hard so they don't produce dust. Some rotors do have problems with pads that aren't ceramic most new cars require them.
Putz, do they make ceramic pads for wilwood brakes?
 

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