Dont know anyone with a dyno..

Im gonna try and see about removing the front drive shaft and the tires and see what happens tomorrow if I can.

This might sound stupid but you should really try to put some tires on it that can be balanced. Your tires might have a higher road force varation. That means that there are hard spots in the tires. I have 35's and I have pretty much the same vibration because they did a static balance when they shipped them which means they are only balanced on one side. Also did you say that your check engine light is on? A mis-fire might cause a shake. What kinda plugs do you have in it?

No misfire or CEL, have denso plugs and wires in it.

See, sometime ago I had swapped for a set of 16's that rode smooth on a friends truck, really didnt help much so I gave them back. Then I had the axle shaft on the pass side replaced and it made a world of difference..but the vibration although lessened still exists.

Im gonna remove all the tires when I can and jack it up and see.

I guess this is what people are calling the flexplate? It's the main plate that transfers power from the driveshaft to the torque converter.

Has this always been an issue since you've bought the truck? I'm still suspect about the engine since you mentioned that it's not the original but a replacement. Without knowing the background of the installer, they could've easily left parts out or not torqued to spec.

I think if the flexplate was not balanced (or anything else in the engine) the vibration would show up at different speeds but the same engine rpm.

So if you go 60 on a backroad then shut the engine off, does it still vibrate?

The engine was installed by the local toyota dealership, when I bought the truck I didnt notice a vibration at all tbh.. 6 months later I had made a few offroad trips, went one some trails that had my truck BOUNCING badly till I managed to slow up-they were hard packed sand and even tho I was going 5-10mpg it bounced the entire truck like MAD.

At that point is when I recall there a vibration coming about, it got worse and worse till we replaced the one axleshaft which was visibly out or spec. Now like I said its still there but much less..

Yes, I did try the driving down a backroad doing 50 and shut it off..smooth as silk. Like I said, when your off the gas no vibe at all-when your on it you get the vibe..

Forgot to mention, I also have a new idler arm, pitman arm and centerlink..all is well up there too, all new balljoints too..

I say you probably snapped a bolt off the flexplate or torque converter... <img src="/forums/images/graemlins/frown.gif" alt="" />

It should be easy to decide whether to consider the flexplate by driving the truck with and without o/d on.

I still think its got to be the transmission output shaft downstream from there.

I have a strong feeling that rolling around with my bent axle ruined my diff. Makes a nice growl and has about 30 degrees of backlash. And I wanted to have my spare cleaned up and swapped in before winter too.. poot.

What about overdrive on or off? Explain please.

I didnt drive more than 1,000 miles with the bent shaft if I recall, b/c I pretty much didnt drive the truck at all for a good year or so..

If I snapped a bolt in either of those..geez.. No way to tell is there besides cracking the trans open. I do know that if I have the truck on stands and just put it into drive with no load the driveshaft seems absolutely fine, infact I watched it spin no problem. Maybe i should try and see if anything moves with cruise locked at about 25mph with the truck in the air?