Driveline Vibration

[pmpski_1]

Any update on this jholley?

[jholley]

Not yet. Truck is at the tranny shop for an unrelated issue. It's getting a completely different tranny/torque converter. While it's there they are going to take a look at the rear end to make sure it's right too. (they rebuilt it and the trans) I won't have it back until next week. I'll be sure to post the results.

[pmpski_1]

Sweet. I'm very interested in the outcome.

[cpetersen]

I found a race shop the makes the u-bolt wedges. You can get any degree set up you want. You can also get lowering block wedges, it should solve our problems. Brian Vickers dad owns this place. cvproducts.com and go under chassis and you see it under rearend wedges. They are kind of skick and expense. Good luck.

[100mph]

Hey any updates on this???

I have a similar problem- vibration shaking mirror and felt in seat and floor between about 1800 to 2000 rpm in 1st, 2nd 3rd and 4th on a 700R4 freshly built mated to a newly built 402 BB, new and balanced one piece drive shaft (not sure of angle)

Anyway.... any updates?

[cpetersen]

Haven't done anything yet, i'm going to put rear disc brakes on the truck. When i pull out the rear end to take the drum backing plates off and collect all of the parts, then i will do it. Just takes money. I'm just working on other things on the truck right now. My buddy works for the roush guys, one the nationwide series cars. It needs to have about 6 degrees to the pinion angle. I have the rear end rebuilt in mine and it still did this. Took it back to the guy that rebuilt it and he said the exact same thing. My driveshaft angle is too straight. It causes a harmonic vibration problem.

[Street Smart]

I see there was never a solution posted, curious how things turned out...

[sleepertruck72]

Originally Posted by Street Smart

I see there was never a solution posted, curious how things turned out...

x2... I had a bad tranny mount that caused a vibration but my truck isnt lowered so it more than likely would not be the same case. I did have a vibration on a seperate occasion though after having my driveshaft shortened for a 700R4 swap. It happened at highway speeds. I learned through a friend that my u-joints werent "clocked" correctly. I had no idea that the u-joints have to be happy or they vibrate Luckily we were able to rotate it to where the joints were happy and the humming/vibration went away I hope your problem was fixed as well !!!

[Hubscrub]

the OP hasn't been on since 3-18-11

[Dunenutt]

Looking at his sig line, he sold it. We may never find out.

I'm having a similar problem, with the opposite altitude.

Mine is raised 4" and shakes crazy. I have spent 8 days cutting, welding, raising, lowering,and cussing, I dream in angles. I have spent countless hours on Google, and in driveline shops. I also am developing nice abs from getting up and down from a creeper.

I gave up, and broke out the benjamins. I am having a ferd super duty shaft built! It will leave the transmission, through the crossmember, to a superduty carrier bearing, into a double cardan joint (CV joint), and down to the rear end. If that does'nt work, I will take out a loan, and have a CV put at the bottom for good measure.

Drivelines are the Devil !

[Street Smart]

I saw he sold it, but by posting on his thread i figured he would get an e-mail and maybe let us know.
Bringing it back up hopefully other will chime in too. But no joke, this stuff can give u a headache. lol

[fixit-p]

There are several post within this thread explaining how to properly set up pinion angles. here is a good thread as well http://67-72chevytrucks.com/vboard/s...=220466&page=2

[Street Smart]

Originally Posted by fixit-p

There are several post within this thread explaining how to properly set up pinion angles. here is a good thread as well http://67-72chevytrucks.com/vboard/s...=220466&page=2

Ive read it, VERY informative! thanks. I`m bringing my truck to our alignment guy so i can use his drive on lift to re-measure my angles. Kinda lazy to use my lift with 4 cinder blocks. I will post my measurements.
Thanks again.

[chopnchaneled]

I had the same problem of a vibration between 1800 and 2000 rpms
turned out to be the converter on my 700r4.

[Street Smart]

Originally Posted by chopnchaneled

I had the same problem of a vibration between 1800 and 2000 rpms
turned out to be the converter on my 700r4.

Mine is more of a MPH vibration, it was a problem I`ve had before and after my motor/tranny swap. In overdrive or drive its there about 65-70 mph.

[CC69Rat]

I have both a C10 and an S10 that are dropped significantly. I found this site with my S10 -- but these should also work with the C10. (At least it explains the concept and much easier than shortening your driveshaft. )

http://www.jagsthatrun.com/Pages/Parts_S10-301.html

this site will also explain drive line angles, pinion shims, etc. Check it out. My S10 is an extended cab and I have their Pinion angle kit (same two piece driveshaft with carrier bearing) .. my point is it sounds like a driveline vibe to me. I used all their products when I dropped my S10 and it rides like a caddy. It's actually smoother now than it was factory. Bilstien shocks, etc. Their parts are incredible. Everything I need will come from them. Super fast shipping, etc.

I'm not associated with them in any way, just really happy with their products. Hope it helps.

Their Pinion kit
http://www.jagsthatrun.com/Pages/Par...aft-Align.html


Cool stuff man ..

[brad_man_72]

ex cab 2wd s10s are notorious for eating rear double cardain joints (i rebuild about 3 a week), espeially if lowered or even zq8. We won't warranty our shafts unless the pinion angle has been corrected. The s10 shaft has very little in common with a 2 piece c10 shaft.

if the exhaust is mounted too solid it can cause a vibration also, we have had this problem with limo manufacturers.

[CC69Rat]

Just trying to help with the vibes.. If nothing else help with the logic as to why a lowered truck, lifted Jeep, etc. Can have driveline vibrations if the pinion angle is incorrect.
Posted via Mobile Device

[Street Smart]

My truck had the vibration from before i owned it, it was stock height. When i asked the guy about it he said he had tryed a few things(new rims, balancing the tires) but never figured it out. He said he just hardly drove that fast, to let it bother him, lol.
Since i own the truck I`ve changed to front disc, new rear drums, lowered 3/5 drop(spindles F&R springs) swapped axles, different D-shaft, new tires. The vibration was not terrible, It got worse after my LS/6L80E swap. I measured all of my angles before with the old set up and again after the new set up. The trans is down 2 more degrees then before, the trans is almost against the floor (really big trans!, low hump floor). So I`m pretty sure my problem is in the drive line angles.

[cpetersen]

This is what the shims look like. I'm going 4 deg, the rearend guy said i should go 6 deg. I'm going to try 4 first. My rear disc are coming next week. I planned on doing it next weekend. We will see.

[fixit-p]

Originally Posted by cpetersen

This is what the shims look like. I'm going 4 deg, the rearend guy said i should go 6 deg. I'm going to try 4 first. My rear disc are coming next week. I planned on doing it next weekend. We will see.

Instead of guessing what you need why not just take some measurments with one of these...



That way you'll know for sure what needs to be done and where.

[CC69Rat]

Kinda cool picture to explain it, makes sense to me.

The angles of the transmission output shaft and the rear pinion should be equal and opposite (if trans points down at 3 degrees, pinion should point up at 3 degrees).

The relationship of the driveshaft to the output shaft or pinion should never be 0 as it will lead to U joint failure (no lubrication)

The ideal pinion angle (relationship of driveshaft to rear pinion) should be 0 or -1 degrees for a normal street used car. If you haul heavy items, of course this could impact the angles at times but should be single use scenario. Just speaking general ride height.

[Street Smart]

^^^^^^^^^^^^^ great pic! and info.
Took some measurements to day. The drive on lift seemed to be level using my angle finder. wish i brought a long level, but any way i got this:

trans- down 2*, front shaft down 3*, back shaft 0*, pinion up 4*.

Its hard to get an accurate place to measure the trans angle, nothing looks parallel to the output shaft. So i figured where the bellhousing mounts to the block should be perpendicular, safe to assume?

[CC69Rat]

Street Smart - I'd try 3deg or 4deg, they're cheap enough maybe get both and see which is better ? You just don't want to zero out. I bet 3's would do it. .. kinda split the difference in the pinion and the #2 shaft. 2-3deg you should be fine. My S10 runs at 1-2deg at the pinion and it's smooth as glass at all speeds.

If you think about the idea of dropping a truck (or lifting really) and what happens all parts considered .. looking at the picture above, just remember that pinion angle doesn't change unless you tilt the rear end housing a little to accomodate the geometry changes that come with the drop / lift. You get a little bit of a change from the 'swing' of the trailing arms but on a leaf truck I'd think it would be more noticable. Ex. 3" drop blocks still make the rear end sit the same as it used to 3" higher than it is post drop. That would make a lot of changes in the angles of a two piece drive shaft. S10, C10, golf cart, Jeep .. whatever ..

I am not sure but I think the C10 drop arms you can get from PB or CPP, etc. I think they actually have this built into the saddles .. I could be wrong.

[Street Smart]

I`m gonna order some different angles and go with your suggestions CC69. Thanks for all the input everyone!!