Thread: engine/trans shake when burning out

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How much room do you have with the yoke going into the transmission? Are you getting movement of the rear end clockwise and bottoming out the drive shaft?

Not for nothing,but the off road/monster truckers have proven that you don't have to have the drive line in line with each other as long as it is the same degree angles under power.Looks weird as all get out,but I guess it works.

There is a lot of slip room on the trans yoke. I forget exactly what I set it up with, but I just used a standard recommended amount, I'd guess maybe 1.5 inches or so.
Now I'm trying to post a current pic with sway bar and all.

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very difficult to see everyting in this pic, I had the bed hanging from my garage roof trusses right above my head when I was doing this work, so it was impossible to get a good picture.

Nice set up, sorry to hear of the problems, I,ve built mine out of spare junk, and came out ok. I also was wondering about the yoke travel distance. 1.5 seems like a lot but may be correct, I would imagine that would change with suspension travel which I would assume you do not use alot of. Like you its been awhile since I set mine up., all I did was add a gear vendors, shortened driveshaft, etc. now don't hold me to this, but I believe the yoke travel was setup at .75. Maybe it is as mentioned before driveshaft wrap up if that is even possible.Anyways just following this thread. Interesting.

I could be wrong, but that panhard bar is really going to put things in a bind as you get any suspension movement. If it is set up neutral at static ride height, considering the arc of travel it is going to pull the center of the rear end over toward the drivers side putting your triangulated 4-link joints in a considerable bind. I don't believe it has anything to do with this shake problem, but I believe that you introduced a new problem by installing that panhard bar, just my opinion.
If it were mine I would drop the tranny and check the clutch for evidence of chatter, and the pilot bearing to be sure your needle bearings aren't toasted.

Probably not part of your vibration problem, but the panhard bar seems short. Looks like it could cause the rear end to move side to side as the suspension goes through it's travel.

Roger you beat me to it. lol

well your absolutely right about that panhard binding during suspension travel. As you can see in that photo it isn't even bolted up in that position because the suspension is all the way down since I had it on stands working on it, and it's arc is so far off at that point I can't even connect it. I set it up though with the suspension up at ride height, so then when I went to finish the job I couldn't even get the bolt through without actually setting the bed on the frame again and then squeezing under the vehicle and putting the bolt through from there.
That's another reason I wanted to switch to heim ends on those links. At first I didn't and I put that panhard on and used a jack to push the axle through it's travel range and watched the joints. They were twisting so hard at maximum travel I was worried I'd fatigue them and end up snapping one off some day on the road.
I really just put the panhard on there because I was out of ideas of what to do and I thought if that helped stabilize the rear more it couldn't hurt.

I would definitely take the panhard bar out and leave it out. The purpose of the triangulated 4-link is to ensure no side movement of the rear end, so you're just causing yourself problems by adding that bar, and doubling the potential binding by making it so short. As a point of reference, my Jeep has OEM "track bars" which is just their name for a panhard, and they run from the frame rail on one side, extending all the way to the most extreme point on the axle tube to minimize side travel on articulation. They're necessary because the suspension is parallel links, and one is anchored driver's side, the other passenger side to offset the side shift of the axles on the road, to maintain tracking to the extent possible.

Grasping at a straw here but.... Inspect the slip yoke on the driveshaft.. check for damaged or broken splines.
If ok, head in for the clutch.

Plenty of angle on the upper bars, all the panhard bar is doing is creating one more potential bind, as Rog mentioned.....

Everthing looks pretty much hunky-dory to me back there. I think 'rspears' made a good suggestion.