Shake/Vibration when Towing

[HotWheelsBurban]

It's gotta be something in the geometry somewhere, front end, drive line, wheels/tires, that's just a little bit off, so you don't notice it except when it's amplified by towing....

 

[Hipster]

Used to have to tell contractors etc to put all their crap and tools back in their vans , then go get an alignment. I'd kinda be thinking the same thing here, a few pounds in the bed to simulate some of tonque weight.

 

[fancyTBI]

Ok, just got off the phone with Tom Wood’s Custom Driveshaft, I think their in Idaho. Gave him my numbers and right away he knew something was wrong and the transfer output number was it. He said literally everything stock is about 5°.

My 11° number was wrong, way wrong, found a more accurate place to read. Mine is 5°.
That being said, this guy went through at least 30 minutes of taking information on truck, did all kinds of calculations and said driveshaft is perfect and Balance Shop saying I needed a new one was complete BS.
So in the end, he believed the wheel shake was it either needing a alignment tweak or a steering stabilizer. I’d say this is good news considering. Pic below showing updated correct numbers.

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He said 0° is no good and need to reduce pinion 2° to get to 5°. But, even correcting this, his opinion was that wasn’t cause of wheel shake when towing.

Glad you got some good answers today. Sorry for the trouble you’re having, but this thread has been a great read and I’ve learned a thing or two.

 

[Caman96]

Glad you got some good answers today. Sorry for the trouble you’re having, but this thread has been a great read and I’ve learned a thing or two.

Thanks, me too. Not happy with Driveshaft Balance shop, with what at least seems like, misleading info on driveshaft. Makes me wonder if it even needed balancing.

 

[Schurkey]

He said 0° is no good and need to reduce pinion 2° to get to 5°. But, even correcting this, his opinion was that wasn’t cause of wheel shake when towing.

He's the expert, not me. He says reduce pinion angle 2 degrees...I guess that's what you should do.

"I" would want to drop the pinion angle 3, maybe 4 degrees, (from 7 to 4, maybe 3 degrees) so that when it torques "up" in front under load, it matches the 5 degree angle at the front of the shaft.

 

[Caman96]

Well I went out, loaded up trailer, to be able to measure with load and without. Truck ended up spun around in driveway. Now I have a different reading on pinion and slight difference on driveshaft BUT they were the same with and without trailer load. So before I decide on to shim or not, I ordered a small digital tool. The iPhone is accurate. It’s problem is it’s size, and the digital ones are very small and magnetic, cheap enough too. Gonna wait for that, tow trailer to a better, flatter area to hopefully take better numbers. Literally, spinning truck in driveway, I got different numbers.
If anyone is interested, as I was looking for torque for u-bolt straps, most I found online was people saying just get it “tight”. I ended up with a consensus of 16-19 ft. lbs. I did 17, but noticed this on the Spicer site.

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[Schurkey]

If anyone is interested, as I was looking for torque for u-bolt straps, most I found online was people saying just get it “tight”. I ended up with a consensus of 16-19 ft. lbs. I did 17, but noticed this on the Spicer site.

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Kinda depends on the method of securing the U-joint. Do you have U-bolts, or do you have straps?

Some applications have U-bolts where the nuts are tightened on the back-side. Your quote from Spicer specifically mentions "U-bolts".

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Other applications have straps where the bolts are tightened from the front.

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Gonna be REALLY difficult to screw-up a U-joint cap with the straps 'n' bolts. The U-bolts and nuts, sure.

 

[Caman96]

Kinda depends on the method of securing the U-joint. Do you have U-bolts, or do you have straps?

Some applications have U-bolts where the nuts are tightened on the back-side. Your quote from Spicer specifically mentions "U-bolts".

You must be registered for see images attach

Other applications have straps where the bolts are tightened from the front.

You must be registered for see images attach

Gonna be REALLY difficult to screw-up a U-joint cap with the straps 'n' bolts. The U-bolts and nuts, sure.

One guy did in another Forum after someone “joking” said torque was 56 lbs. His next post after snapping a bolt was physically threatening the joker.

 

[Orpedcrow]

Did you get one of those little square digital angle things? Like you see people using on table saws

 

[Caman96]

Did you get one of those little square digital angle things? Like you see people using on table saws

I did. They are small and magnetic. The iPhone is mechanically accurate, size sucks and you have to be careful with the buttons on the sides interfering.