Went to see a nice M37, it has the dreaded death wobble

[Don1357]

Near Denver. If somebody could suggest a mechanic to diagnose it would be helpful.

Everything looks great, it does leak oil here and there but nothing terrible nor puddling forming. I wanted to test cruising speed at 45mph but once it went past 40 the front just starting shaking left and right something fierce. And I mean, unbalanced washing machine on spin cycle sort of fierce. I brought the speed down, unclenched my bottom, and was able to bring the speed back up without most of the wobble, but later it came again just as fierce.

Best guess something is not tight and when the right vibration hits it, things go haywire.

[EDIT] Chatting to the current owner who doesn't drive it much and usually below 35mph, second guess is that it needs a front end alignment and wheel balancing.

As I said, I would like to take it to a mechanic to see what's what before I decide to buy it.

 

[NDT]

M37s are not known for this at all. Something is very out of whack. Should be an easy fix.

 

[67Beast]

Stock NDT tires? If so they could have some flat spotting from sitting. I know it takes a bit of driving to get them knocked back round. Plus the M37's don't like much more speed than 40-45 after that they sound like they are going to come apart. If it is death wobble, it usually is due to tie rods or bad king pins.

 

[Don1357]

I briefly crawled underneath but could not spot anything amiss with the naked eye. Which honestly, it doesn't say much... These guys were gone by my army days but I recognize the overbuilt construction, I'm hoping that front end alignment/wheel balancing would cure it. If anything I'm sure they are not helping.

Follow up question: is there a transmission replacement that could fit in without modifications? The gearing jump between 3rd and 4th is significant.

 

[wildcatter2009]

As previously stated, likely tie rod ends or loose king pin bearings. To check, have someone turn the steering wheel back and forth while you watch tie rod ends for looseness. For kingpins, jack up the front axle and grip the tire at top and bottom. Try to tip wheel in and out to check for looseness.

 

[JimC2]

"Follow up question: is there a transmission replacement that could fit in without modifications?"

No.

 

[HoveringHMMWV]

Pics? Would love to see your possible new project.

 

[CA-Deplorable]

Near Denver. If somebody could suggest a mechanic to diagnose it would be helpful.

Everything looks great, it does leak oil here and there but nothing terrible nor puddling forming. I wanted to test cruising speed at 45mph but once it went past 40 the front just starting shaking left and right something fierce. And I mean, unbalanced washing machine on spin cycle sort of fierce. I brought the speed down, unclenched my bottom, and was able to bring the speed back up without most of the wobble, but later it came again just as fierce.

Best guess something is not tight and when the right vibration hits it, things go haywire.

[EDIT] Chatting to the current owner who doesn't drive it much and usually below 35mph, second guess is that it needs a front end alignment and wheel balancing.

As I said, I would like to take it to a mechanic to see what's what before I decide to buy it.

Near Denver. If somebody could suggest a mechanic to diagnose it would be helpful.

Everything looks great, it does leak oil here and there but nothing terrible nor puddling forming. I wanted to test cruising speed at 45mph but once it went past 40 the front just starting shaking left and right something fierce. And I mean, unbalanced washing machine on spin cycle sort of fierce. I brought the speed down, unclenched my bottom, and was able to bring the speed back up without most of the wobble, but later it came again just as fierce.

Best guess something is not tight and when the right vibration hits it, things go haywire.

[EDIT] Chatting to the current owner who doesn't drive it much and usually below 35mph, second guess is that it needs a front end alignment and wheel balancing.

As I said, I would like to take it to a mechanic to see what's what before I decide to buy it.

Was the M37 by any chance the one located in Bennett, Colorado? I was also interested in an M37 in the Denver area. If it's the one we're talking about, it's going on an auction site at the end of March. I saw a video of the driver driving it, and if you look closely, you'll see him turn the steering wheel a couple of times before the front wheels start to react. The guy did a basic figure 8 in the vehicle with a reverse too. All the times he turns the steering wheel but the front end is slow to react. There was something definitely wrong with the front axle.

 

[JimC2]

Sounds more like something wrong with the steering box.

 

[CA-Deplorable]

Sounds more like something wrong with the steering box.

According to the seller, the M37 needed a Pittman arm

 

[G744]

With all that said, it could be the following, not is any specific order:

Worn or misadjusted steering box.
Drag link wear.
Drag link pivot wear.
Front knuckle bearings loose (It doesn't have "king pins").
Tie rod end wear.
Toe out of spec.
Loose wheel bearings.
Spring wear causing improper caster.
Tires hopelessly out of balance.

None of the above are all that serious to fix.

G744

 

[CA-Deplorable]

With all that said, it could be the following, not is any specific order:

Worn or misadjusted steering box.
Drag link wear.
Drag link pivot wear.
Front knuckle bearings loose (It doesn't have "king pins").
Tie rod end wear.
Toe out of spec.
Loose wheel bearings.
Spring wear causing improper caster.
Tires hopelessly out of balance.

None of the above are all that serious to fix.

G744

It is viewable on the auction website. It's a good looking vehicle, very clean!

 

[G744]

The most complex thing on any G741 truck is the original carb. Second on the list is the three-bearing pinon shaft. Third is the original wiring system.

The rest is just shade tree knowledge.

G744

 

[Capt Pat]

Or when somebody tries to wire in a key start to the 24 volt system like they did in the one I just bought, what a wiring nightmare. Something is taking the batterys down, but its easier to fix that your issue, I'm just pulling the bloody crap outa it and put it back original.