Driveshaft Out-Of-Phase?

[gavin]

Since driveshafts aren't really listed in any particular section, I figured this would be the best place to post.

To make a long story short, I've been trying to replace my front gkn cv-joint'ed front driveshaft with a double-cardan cv-joint unit.
#1 - purchased Rockford Driveline-made front d-shaft off eBay. Had single u-joint front and rear, but was labeled for Explorers (and had correct 6-bolt yoke to bolt to "cup" on t-case).
#2 - receiving vibes with new shaft. Assumed was due to u-joint angles. Replaced u-joints anyway; vibes continued.
#3 - took shaft to local shop to get double-cardan cv put on. They found the necessary parts to do this.
#4 - still receiving vibes. Had shop re-balanced shaft. Vibes still continue.

So here is where I'm at. Last thing I can check, is if the shaft is "in phase."

 

[gavin]

maybe the shaft is out of phase?
I'm not sure how to check, so I did what I thought would tell me.
I used my angle-finder on 3 parts of the shaft; the diff u-joint, the inner cv u-joint, and the outer cv u-joint.
I then put the angle finder on the garage floor to make sure it was also level.

diff u-joint (~1.5*)

inner cv u-joint (~5*)

out cv u-joint (~5*)

floor (it is 0*, needle was still bouncing when I took the pic)

there is a ~3.5* difference between the diff u-joint (~1.5*) and inner cv u-joint (~5*). Virtually no difference between inner and outer cv u-joints.

so it looks (to me) like the shaft is not in phase. If it was not in phase, would it cause vibes, even if it balanced good?

 

[gavin]

I then rotated the shaft 90*, and measured again.

diff u-joint (~ -1*)

inner cv u-joint (~ -1-1.5*)

outer cv u-joint (~0*)

now the inner cv u-joint and diff u-joint are almost identical, with the outer cv u-joint being at a different angle.

 

[IZwack]

The problem isnt phase --.

The second gens came with a CV or double cardan driveshaft stock -- which requires the differential pointing at the transfer case. Now that you've changed to a single cardan, you have to change the angle of the differential and point it down a few degrees. In your situation where you are using a single cardan driveshaft, the differential must be rotated up (the pinion end pointed up a little bit) so that the differential points directly at the transfer case -- give or take 1 degree.

 

[gavin]

The problem isnt phase --

Because you now have a single u-joint at each end, the driveshaft angle is now incorrect. With a single-cardan driveshaft, the transfer case and the differential must be within 1 degree (or less) from parallel with each other.

The second gens came with a CV or double cardan driveshaft stock -- which requires the differential pointing at the transfer case. Now that you've changed to a single cardan, you have to change the angle of the differential and point it down a few degrees.

#3 - took shaft to local shop to get double-cardan cv put on. They found the necessary parts to do this.
#4 - still receiving vibes. Had shop re-balanced shaft. Vibes still continue.

 

[IZwack]

Ahaha sorry. Have you double checked the angle on the differential and the transfer case?

 

[gavin]

Ahaha sorry. Have you double checked the angle on the differential and the transfer case?

haha, it happens.


these angles are rough estimates.

the left side is the diff, right side t-case.
These were not taken on level ground, which could be why the pinion angles downwards (the driveway is slightly sloped, which would explain the pinion angle).

roughly 9* operating angle (right...?)

 

[IZwack]

So 4 degrees of difference? If so, thats a bit much. Ideally you should not have any angle difference at all but it is advised to have a 1 degree difference because in the real world, the U-joint caps must be lubricated and that 1 degree forces them to roll around a little and move some grease around.

I know you may not have touched the diff and transfer case at all, but check the transfer case mount under the tailshaft housing -- maybe thats worn out and flat (which increases the angle of the transfer case).

 

[gavin]

So 4 degrees of difference? If so, thats a bit much. Ideally you should not have any angle difference at all but it is advised to have a 1 degree difference because in the real world, the U-joint caps must be lubricated and that 1 degree forces them to roll around a little and move some grease around.

I know you may not have touched the diff and transfer case at all, but check the transfer case mount under the tailshaft housing -- maybe thats worn out and flat (which increases the angle of the transfer case).

I had some numbers mixed up/incorrectly calculated.

but yes, roughly 4* difference between pinion and t-case.
Although the operating angle is roughly 9*.
Which should be fine for a d-c cv.

I am pretty sure, though, that the transmission mount bushing needs replaced.

but I have heard that if a driveshaft is out of phase, it can cause vibes.

and with the yokes on the shaft providing different angles, it makes me believe that (atleast part of) the issue is with the shaft itself.

and me not being very driveline smart, want to verify wether or not I am thinking correctly in the issue still being with the driveshaft (which I have put WAY too much money in to....)

edit: oops! it's actually about a 6* difference between pinion and t-case.... I think? (we go by the angles on the inside of the "trapezoid" that the components create, no?)

and you may need to shift-reload the page, because I did change the last pic (it should show 96.5*, not 93.5*)

 

[IZwack]

but I have heard that if a driveshaft is out of phase, it can cause vibes.

Yes it does. But there are a few simple things you can do before you spend more $$ to get the driveshaft cut and re-phased -- like stacking a set of washers under the transmission mount to shim it up a little bit and seeing if that minimizes the vibration.

 

[gavin]

Yes it does. But there are a few simple things you can do before you spend more $$ to get the driveshaft cut and re-phased -- like stacking a set of washers under the transmission mount to shim it up a little bit and seeing if that minimizes the vibration.

well I do hope to get the work done for free.
since only 1 shop has touched the shaft, except for the company I purchased the shaft from.

since I am still receiving vibes, and if the shaft is in fact out of phase, they should fix it at no-cost since it was their mess-up.

another piece of info, that may or may not make any difference; the vibes I feel now (and hear under engine breaking deceleration), sound 100% identical to the vibes when the shaft was a single-cardan.

I do plan on (atleast attempting) to replace the transmission mount next weekend. I was just hoping to get enough info I could take it back to the shop this week.

 

[IZwack]

I've gone through two of those type of angle finder you are using and I always found them difficult because they would "stick" -- tap it a little bit and you get a different angle.

I know you gotta do with what you have and this is why I mentioned stacking a set of washers first under the transmission mount cauz the deviation of error in the phase angle measurements is probably a degree or two.

 

[gavin]

I've gone through two of those type of angle finder you are using and I always found them difficult because they would "stick" -- tap it a little bit and you get a different angle.

I know you gotta do with what you have and this is why I mentioned stacking a set of washers first under the transmission mount cauz the deviation of error in the phase angle measurements is probably a degree or two.

I've used this angle-finder a bit and it hasn't stuck on me... yet.
I'll try and give that a shot though, depending on what the weather does. Although I do hate trying to work on my junk during the work-week.

 

[ericautopart]

Sounds like rockford gave you a drive shaft with a bad head. 99.9% of shops who claim to be able to fix this problem can't. They aren't set up to do it and I think were looking way too deep into this issue. I'd return it to rockford and buy a new one. I had a sale on them a while ago here on EF but no one took to it so if you'd like a new OEM one I'll gladly give you a good price. That should fix your problem there..

 

[gavin]

Sounds like rockford gave you a drive shaft with a bad head. 99.9% of shops who claim to be able to fix this problem can't. They aren't set up to do it and I think were looking way too deep into this issue. I'd return it to rockford and buy a new one. I had a sale on them a while ago here on EF but no one took to it so if you'd like a new OEM one I'll gladly give you a good price. That should fix your problem there..

I wish I could return it, but 2 problems.
#1 - I did not buy directly from Rockford Driveline.
#2 - the shaft has been modified by somebody other than Rockford.

out of curiousity; what do you mean by bad head?
the yoke @ the t-case end of d-shaft has been replaced with a new NeapCo unit.
The CV itself was used, but rebuilt.

 

[ericautopart]

I wish I could return it, but 2 problems.
#1 - I did not buy directly from Rockford Driveline.
#2 - the shaft has been modified by somebody other than Rockford.

out of curiousity; what do you mean by bad head?
the yoke @ the t-case end of d-shaft has been replaced with a new NeapCo unit.
The CV itself was used, but rebuilt.

A lot of the time the rebuilt/used/aftermarket explorer shafts come w/ a Chinese aftermarket head that doesn't hold up and uses cheap bearings. The neapco u joint won't be the cause of the problem. We sell A LOT of remanufactured drive shafts but I won't sell a reman v8 explorer shaft as we'd run into the same problems as you did. Honestly, I'd just buy a new OEM one and you'll be trouble free. I'm sorry you got stuck w/ that issue though I can feel your pain. If you need a new one..I'm here.

 

[gavin]

A lot of the time the rebuilt/used/aftermarket explorer shafts come w/ a Chinese aftermarket head that doesn't hold up and uses cheap bearings. The neapco u joint won't be the cause of the problem. We sell A LOT of remanufactured drive shafts but I won't sell a reman v8 explorer shaft as we'd run into the same problems as you did. Honestly, I'd just buy a new OEM one and you'll be trouble free. I'm sorry you got stuck w/ that issue though I can feel your pain. If you need a new one..I'm here.

problem is, I don't want another GKN cv-style shaft.

 

[ericautopart]

Rockford sells a conversion w/ a slip/stub/flange like I do on a lot of other models but I don't sell them. For the explorers I like to play it safe and stick w/ the OE. You've got a 1997 so I'd imagine you got some use out of the OE style shaft. Either one will solve your problems.

 

[gavin]

Rockford sells a conversion w/ a slip/stub/flange like I do on a lot of other models but I don't sell them. For the explorers I like to play it safe and stick w/ the OE. You've got a 1997 so I'd imagine you got some use out of the OE style shaft. Either one will solve your problems.

that is what I started with.
single-cardan on both ends.
and I've been through 3 (going on 4) of the OEM GKN cv-style shafts.

besides, 96-97.5 (my guess), had double-cardan from the manufacturer.

 

[ericautopart]

that is what I started with.
single-cardan on both ends.
and I've been through 3 (going on 4) of the OEM GKN cv-style shafts.

besides, 96-97.5 (my guess), had double-cardan from the manufacturer.

91-96 did I don't know about 97.5 but I could be wrong. 96 also had a double cardan on one and but 96.5 ish had a flange on the CV side. I had that issue with a member on here actually.

Somthing tells me if your going through that many your buying them used or a crappy reman? Or is your truck lifted?