Shudder at 40mph

[RayGunSlayer]

Hey guys, I wanted to get some opinions on exactly what I should. So ever since I’ve gotten the vehicle, once I hit, and this is exact without any difference each time, 40mph on the dot the truck has what feels to me just like torque converter shutter. I’ve had that on another vehicle and this feels exactly the same. So here is my hypothesis. I at first thought it was torque converter shudder so I replaced the torque converter with a brand new one made specifically for the 4l80e in our vehicles. Come to find out it had the wrong with in the originally. When I pulled it the fluid was mint. I had put about 100 miles on the vehicle before I was able to change it but still would have seen something in the fluid if it was actually torque converter shudder due to material wearing off from slipping. So my thinking is this, that it’s not the tranny either because is dead nuts at 40. I usually am in overdrive at that point but I have tested it by just being in 3rd gear and it’s still there at 40 then too. So my next thing was maybe driveshaft. It felt more in the front since I constantly only feel the shudder in the gas pedal so I took the front driveshaft out and it definitely helped a good bit but it’s still there. So at this point I am either thinking that it’s my transfer case or has to be from the differentials to the wheels somewhere. Just curious as to if anyone has experienced anything like this. Thank you all!

 

[RayGunSlayer]

I should also mention too that the shudder is not always consistent. Like it will shudder from maybe 2-3 seconds and kind of fade away for like a half of a second and then come back. It’s definitely kind of weird. Also, I have 42 inch boggers that are balanced with beads on there right now. I have had a lot of sets of boggers in my life and this is not something that boggers do. No play whatsoever at hubs or ball joints. The shudder does not come through the steering at all just through the gas pedal.

 

[Retiredwarhorses]

You have a shake with 42in Boggers? Really? SMH..lol

 

[TNDRIVER]

I should also mention too that the shudder is not always consistent. Like it will shudder from maybe 2-3 seconds and kind of fade away for like a half of a second and then come back. It’s definitely kind of weird. Also, I have 42 inch boggers that are balanced with beads on there right now. I have had a lot of sets of boggers in my life and this is not something that boggers do. No play whatsoever at hubs or ball joints. The shudder does not come through the steering at all just through the gas pedal.

Could be you balance beads are distributing around the tire at 40. Might want to swap a set of wheels and tires on and see if it is still there??? I think I would have tried that before pulling a converter....the beads don't balance the tires until centrifugal force distributes them around the tire. Just my 2 cents.

 

[simp5782]

You have a shake with 42in Boggers? Really? SMH..lol

Some folks think its supposed to ride like a caddy a AM General HMMWV Brougham editon

 

[Bill Nutting]

Welcome to the best site on the web!
I'm confused (that is my normal state). Are the tires new or original? My 934 came with 10 tires that looked like brand new. They were installed 8 years prior to my buying the truck. The truck had a total of 5,000 miles on it. The problem was, this truck sat on new tires for 8 years in one spot. They were upgraded to radials at Red River. They developed flat spots that I could not fix. I tried under inflation and over inflation and just driving on them. It broke my heart (and bank account) to replace all 10 tires with new ones. My symptom was more of a pounding between 40 - 50 MPH. It was the worst at 45. New tires fixed it. there is a posting on here about grinding the tires round again. It is brilliant how they do it. If I had seen that post it would have saved me some serious dough...

 

[RayGunSlayer]

Well I’m glad that the first thing I get is treated like an idiot. Thank you retired war horse! Anyways I never said it should ride Ike a caddy at all. If that’s the case I wouldn’t have boggers or even a hmmwv because they ride like ass but look cool. On another note bogger shimmy and torque converter shudder is 2 totally different feelings because I’ve had both before. Anyways... it is possible that it’s the balancing beads at that speed but I’ve never felt it before with any of my other vehicles on boggers. I’ve had a Tacoma on 42x13.5r22 boggers for a while. Still possible though. The boggers are also brand spanking new. It truly feels more like bearings grinding or something along those lines. Thank you to the guys that actually provide any kind of infomation or help. I may never find out exactly what it is but it never hurts to ask to see if anyone has ever experienced anything like this before. I agree Bill it can be the best site for getting help with hmmwvs especially when you know almost nothing about them but people automatically being an ass doesn’t make matters better.

 

[RayGunSlayer]

Could be you balance beads are distributing around the tire at 40. Might want to swap a set of wheels and tires on and see if it is still there??? I think I would have tried that before pulling a converter....the beads don't balance the tires until centrifugal force distributes them around the tire. Just my 2 cents.

I will most definitely give this a try. I still have the original set of tires that came with the hmmwv so I’ll swap them out and see if it changes anything. Thank you!

 

[DREDnot]

You seem to have tried a few logical tests to try to find the shudder.
I would swap the boggers out with a different set in original size and see if the shudder changes or goes away. Just to be sure .
Second thought comes from your removal of the driveshaft test. I had similar issues that were baffling me and I found NOS front and rear driveshaft assemblies for cheap and threw them in. Issue went away. Ive seen bad ujoints make the weirdest sounds and vibrations...

 

[TNDRIVER]

I will most definitely give this a try. I still have the original set of tires that came with the hmmwv so I’ll swap them out and see if it changes anything. Thank you!

Let us know what you find. I kinda like people that are not afraid of wrenches! Own a few myself.

 

[Action]

Does the shudder go away after 45 mph? If so, likely the tires /wheels.