Front drive shaft

[MaiNiaK]

So I noticed the day I picked up my truck that there was a vibration that started around 45 mph.
I hadn't mentioned it because People would have said its from driving it in the water.

I believe it's coming from the slip joint on the front drive shaft. All the U joints feel good and the back slip joint doesn't have any play. The front slip joint on the other hand does have play. Grabbing ahold of it and pushing up and pulling down you can tell it's not right.

Just wanted to to put that out there if others are having vibration issues.

 

[MaiNiaK]

Has anyone taken out their front drive shaft.
I see there are a few folks that go pick up auction wins or do a lot of highway driving.
Does it make any difference on fuel economy or overall handling on paved roads or highway driving?

 

[Blackmagic94]

Some first gen FMTVs had driveshaft vibrations issues, might want to look into if yours received the updated shafts.

 

[MaiNiaK]

Some first gen FMTVs had driveshaft vibrations issues, might want to look into if yours received the updated shafts.

Thanks Blackmagic. I did read something about that in a real old post on here. That's how I knew to check the front shaft.
How do you figure out if your truck did recieve the upgrade? (Have someone do a vin lookup?)

I figure I'll still want to get a new front drive shaft. I just figured if I was running it on the road hauling loads (wood, compost) it might run better over the road with just a rear shaft and possibly get better fuel mileage. Ofcourse this winter, or off roading I'll want the all wheel drive.

 

[Oxyacetylene]

Look on the data plate. If yours has a D stamped on it, then it received the driveshaft fix. From what I have read on here, all of them should have had that work done. There is a thread on here somewhere that tells all of this.

 

[us4korea]

Just picked up my 97 M1083 and drove it back to CA from KY.After 5 days of driving, I get the vibration around 47-54 and sometimes need to drop below 45 to get it to stop. I can also back off the gas when it first starts and get it to stop, then carefully ease it up to 55-57 with no problems. Then I will hit a bump or change in road and the vibration will start in again. I have the D stamped in my data late so I know that I have the drive shaft upgrade. I also get what I will call a gearbox chatter/grind going down hill at freeway speeds with no or very little throttle.

 

[radbad]

Mainiak - there's a test in the TM called the "driveshaft hinging test". Calls for a max of .020" play in the splines you're referring to. Sounds like you're over that limit. TM recommends to replace.

 

[colorado LMTV]

Did you ever find out if you can run the LMTV with the front drive shaft uninstalled? We need to run an emissions test on the truck and taking off the drive shaft will allow us to do that. Thanks.

 

[Suprman]

Put the truck in "mode" and you can run it without the front driveshaft.

 

[coachgeo]

No you can't drive in normal mode with a driveshaft off. being that it is AWD it will try to send all power to what ever axle is slipping completely. With no driveshaft it senses that as tire spin... thus you will get all power sent to a disconnected axle.