Truck shakes after take off..

[BigBlockDodge]

My 69 W100 shakes pretty bad after i take off and I'm moving along in 2nd gear. (NP 435 4 speed). The shake is not when I am on the clutch, although it shakes there too, but I know how to fix that. This shake is, like I said, after I let out the clutch and I'm in 2nd or 3rd gear. It only shakes when it is under a load, like going up a hill. Between my Dad and I, we have owned the truck for 10 years, and have had 6 different engines in it and a couple different clutch setups, and it has always had the shake problem once you get moving under a load. Just recently I swapped the 4.10 gears out of it in favor of 3.55's. Ever since I have done this, it has made the shake problem even worse. My Dad and I think the problem might be in the transmission, maybe something worn causing it to have some slop which could make the truck shake. Has anyone had this problem, or know a possible solution to fix it? Any help would be much appreciated!

[elacruze]

Most likely your carrier bearing needs replacement, and/or driveshafts balanced.
Are you certain that all your u-joints are tight?

[BigBlockDodge]

The rear diff carrier beatings were replaced when the 3.55's went in. And all of the u joints on the truck have been replaced about 4 years ago and have been kept well greased and are still tight. But the driveshaft could be out of balance

[elacruze]

Sorry, I mean your center support bearing between the driveshafts. When the rubber gets shrunken, broken, overheated, or whatever it allows the driveshafts to wobble in the hole until they spin fast enough to smooth out. A u-joint that's shucked out the needle bearings will do the same thing.

[digdoug]

Since we are talking about a W100,It shouldn't have a rubber insolated center support bearing.
The problem you describe is inherent with devorced transfer cases. What helps is to phase the center driveshaft with the rear driveshaft.Try it and see.Of course,every time you put the TC in low it wil mess up this phaseing...

[BigBlockDodge]

It does not have the rubber center support. I had a d200 that had that. My W has a straight, splined drive shaft.

So how do you go about "phasing" the 2 drive shafts together?
Thanks for the help!

[elacruze]

DOH! I really need to watch that prefix. I've never owned anything with a divorced case, I'll go back home and sulk now.

[digdoug]

LOL!

[digdoug]

It does not have the rubber center support. I had a d200 that had that. My W has a straight, splined drive shaft.

So how do you go about "phasing" the 2 drive shafts together?
Thanks for the help!

Put the transmission and transfer case in neutral,set the brake or chalk tires,go under the truck and turn the input driveshaft until its yokes are lined up the same as the rear driveline.Shift the TC into hi and double check that they are still aligned.

See figure 13 at the link... http://www2.dana.com/pdf/J3311-1-HVTSS.PDF

[BigBlockDodge]

digdoug, I did what you told me to do and....the problem is solved!! I cant believe how simple a fix it was! My rear driveshaft was actually off by about 1 spline, so I had to unbolt it from the rear end and fix that. The center shaft was off by a little bit, so I aligned it by a level to the rear driveshaft.
Thats 1 more "bug" to work out off my list! Thanks again!!

[digdoug]

I love it when the simple stuff works!

[elacruze]

That's a pearl of wisdom to keep in the box, for sure.

[RussRoth]

This issue has come up a few times before. I'm just wondering what causes this? I have been around 4x4's since long before I was a teenager and I draw SS now, so a year or two. I have never seen, heard of or experienced this condition on any I have been around nor has anyone else I know except on the forums. I grew up on a dairy farm and we used 4x quite bit in the rainy part of the year and always with a divorced case. Three different 4x's during that time growing up, even more in the intervening years and never had an issue. I'm not saying it doesn't happen, just wondering why I never heard about it before? And why no one in my circle around here have had it occur? Now the dreaded DW (death wobble) is a different story.

[BigBlockDodge]

I never heard about it before until digdoug told me about it My W100 is the only divorced T-case truck around here that I know of, so I dont know of anyone locally that is knowledgable about them. But like I said, my truck has had the shakes ever since my Dad and I have had it. But it was sure easy enough to fix! It's a different truck now!