Sloyds85fifth
Member
I don't have a go pro, would be a good thing to try though
85 Fifth Avenue still vibration in the steering wheel at speed after thousand$ in repairs
- Thread starter Sloyds85fifth
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volare 1977
Well-Known Member
I wonder about the frame where it attaches to the steering box. Some of those welds are not so great.
I already mentioned that, earlier in the thread. It can happen on the M-body, but these things have other issues that happen with a lot more frequency.
5thtimesthecharm
Well-Known Member
I know brakes have already been mentioned but I had the same issue, except mine started at 70 and faded out at 85, no brakes applied.
Im not sure why it translated to the front and steering wheel vibration, but it was my rear shoes being too tight, and one was tighter than the other.
I adjusted them even then set both about 4 notches back, and the vibrations are gone. It was the only thing I did as i wasnt trying to fix the vibration at the time, just re-adjusting the rear brakes. Noticed the vibrations were gone right after during the test drive.
Im not sure why it translated to the front and steering wheel vibration, but it was my rear shoes being too tight, and one was tighter than the other.
I adjusted them even then set both about 4 notches back, and the vibrations are gone. It was the only thing I did as i wasnt trying to fix the vibration at the time, just re-adjusting the rear brakes. Noticed the vibrations were gone right after during the test drive.
Sloyds85fifth
Member
Yes another fella had mentioned that and that is some great input. I'm definitely going to have the mechanics look into that. So I had the rotors and calipers put on the front because one of them was seizing up. I was hoping that would get it. It did not lol. Even had shocks put on the back at the time. So it's got four new shocks on it now. In addition to the all new brakes etc. So the next thing I'm going to look into is another mechanic at noticed that all the bushings under the front are shot. I don't know how I had noticed it. But several other mechanics hadn't noticed it either. But he showed me and they are blown out. So I'm going to try those bushings. The drive shaft bushing I think is especially suspect. It looks really worn out like there's been a lot of movement there. So I'm going to have those bushings done. Then after that I guess it's the frame shop
There is no driveshaft bushing. That's the rear engine/transmission mount. Use the civilian version, not the police version.
A heavy front vibration that's not from the tires or wheels, or any other front suspension/steering component is generally incorrect or insufficient caster (camber wears out the tires more than anything). The factory caster settings for the M-body are a cruel joke. You can easily add 2 or 3° + on these things, and that's still not enough. I would suggest keeping them the same, side to side.
This can happen for any number of reasons:
- Most common on the Fenton and early Kenosha cars is a bent or possibly even a twisted shock tower. The correct repair is to figure out how it's bent and how bad. Shims won't help insufficient caster (see below). Have that repaired, if possible, then readjust caster and camber accordingly. This obviously did happen to civilian and police models alike, and the only way to determine it is to have everything measured.
- The FMJ were fairly susceptible to collision/severe impact damage that isn't readily apparent. If the car hit a deer or a fleeing perp, that probably wouldn't do it. If it went into the ditch in a bad snowstorm, she probably got messed up. We'd never know that today, unless you know the entire history of the car.
- Poor alignment repair. If a mechanic threw it up on the rack for a 2-whl thrust alignment, and didn't measure anything but the toe - or replace any worn parts - it could be way out of whack. Get the tape measure out, and get to work.
- One final thought - I've read comments here about shifting the k-frame to adjust front settings. I would say don't mess with it unless you absolutely have to. The entire suspension on a torsion-bar RWD Chrysler passenger vehicle is fully adjustable, and monkeying with the k-frame location - even if you could remove those bolts without breaking them - would not provide the adjustment(s) needed, unless measurements prove that it's not mounted square to the subframe rails (assuming the rails are square themselves). However - If it's not mounted square, it's important to figure out why the hell not, before proceeding with that operation. I've never heard of that problem on any legacy RWD Mopar, unless the car was in a bad wreck, or JimBob or BillyBetty got his grimy paws on it, trying to LS swap it or some other BS.
A heavy front vibration that's not from the tires or wheels, or any other front suspension/steering component is generally incorrect or insufficient caster (camber wears out the tires more than anything). The factory caster settings for the M-body are a cruel joke. You can easily add 2 or 3° + on these things, and that's still not enough. I would suggest keeping them the same, side to side.
This can happen for any number of reasons:
- Most common on the Fenton and early Kenosha cars is a bent or possibly even a twisted shock tower. The correct repair is to figure out how it's bent and how bad. Shims won't help insufficient caster (see below). Have that repaired, if possible, then readjust caster and camber accordingly. This obviously did happen to civilian and police models alike, and the only way to determine it is to have everything measured.
- The FMJ were fairly susceptible to collision/severe impact damage that isn't readily apparent. If the car hit a deer or a fleeing perp, that probably wouldn't do it. If it went into the ditch in a bad snowstorm, she probably got messed up. We'd never know that today, unless you know the entire history of the car.
- Poor alignment repair. If a mechanic threw it up on the rack for a 2-whl thrust alignment, and didn't measure anything but the toe - or replace any worn parts - it could be way out of whack. Get the tape measure out, and get to work.
- One final thought - I've read comments here about shifting the k-frame to adjust front settings. I would say don't mess with it unless you absolutely have to. The entire suspension on a torsion-bar RWD Chrysler passenger vehicle is fully adjustable, and monkeying with the k-frame location - even if you could remove those bolts without breaking them - would not provide the adjustment(s) needed, unless measurements prove that it's not mounted square to the subframe rails (assuming the rails are square themselves). However - If it's not mounted square, it's important to figure out why the hell not, before proceeding with that operation. I've never heard of that problem on any legacy RWD Mopar, unless the car was in a bad wreck, or JimBob or BillyBetty got his grimy paws on it, trying to LS swap it or some other BS.
Sloyds85fifth
Member
I agree. I am beginning to suspect the shock towers a lot more
Let's hope not. First thing to do is measure, measure, and measure. Get the FSM out and your trusty tape measure, and start with ride height, then measure pitman arm to idler arm (parallel to the ground), then measure the k-frame's mounting and everything else. Adjust the ride height and the idler arm bracket as necessary, then start over. If all of that is fine, then look into your steering gear and tie rods, ball joints, control arm and torsion bar bushings, and see what you need there. Make certain your rotors and rims are good on run-out. Get that all fixed up, then re-measure all of it. You should be ok at that point. Get it aligned to (not within) spec, and have them add at least 2 or 3 degrees of caster, same number at each side. Try it out. Adding caster should eliminate the "shopping cart" effect that seems to create a lot of headaches with older Mopars.
If none of that solves the problem, then you have to have them take a look at the shock towers, the k-frame itself, the engine mounts and mount brackets, the subframe rails, etc.
