Please help diagnose a driveline vibration

[Hokiefyd]

There's been a vibration in our CR-V ever since I've owned it (which has been for about 50k of its near-100k miles). It's probably been there since new. You can feel it start to flutter at about 60 mph, it's pretty noticeable at 63-67 mph, and it's beginning to flutter back out by 68-70 mph. You can feel it in the seat/floor, and it doesn't matter how the tires are rotated...it's not a steering wheel vibration, but sort of a "whole vehicle" flutter. The vibration *sometimes* seems to come and go...like it's not completely consistent. There's always some sort of a flutter or vibe in this speed range, but it seems to be worse or better depending on some variable(s) that I can't put my finger on.

I've told myself a story about it ever since we owned it. It had a set of tires that was at least half worn when we bought it, so I assumed it was tires. Then with the second set of tires that I installed, the vibration was still there, and I probably assumed it was the tires. I had Sears re-balance those at least once, but to no avail. Now I've had a new set of tires installed and the vibration is still there. So I'm pretty sure that it's in the vehicle.

This is an AWD CR-V. Last night, I rotated the propeller shaft 180 degrees relative to the rear differential unit. I'm pretty sure the vibration got a bit worse, so I think I'm on the right track. I then put two hose clamps around the driveshaft, to add some weight, and now I get a similar vibe at about 58-60 mph. So again, I think I'm on the right track. My next plan is to completely remove the propeller shaft and see if it goes away. This AWD system is both mechanical and reactive, so removing the prop shaft essentially turns it into a FWD vehicle.

Am I doing the right things here? Any tips on balancing the prop shaft if that does indeed appear to be the problem? (The center carrier bearing appears to be in great shape, as do the rear differential unit mounting bushes.)

 

[Jim_Truett]

Yes, run it without the prop shaft installed to rule it in or out as the cause. Check the u-joints in the prop shaft for notchiness and binding. It's pretty common for them to get rough, and replacement generally consists of replacing the whole shaft. Rockford Driveline sells the replacement u-joints if you feel like taking on the replacement of the factory staked in units. Rockford

 

[SwampSurvivor]

As long as the PDU doesn't leak out it's fluid with the propshaft disconnected - yes, that will help eliminate.

However, if the problem is the rear differential (Those honda systems are pretty picky from what I hear), you could also eliminate the noise by removing the drive shaft.

 

[Kool1]

The replacement u-joints I bought from Rockford for my 03 CRV are made in China. Honda does not sell the u-joint alone. I know the guy at a local wrecking yard and bought a complete driveshaft for $40.00. The vibration I had was at a lower speed but, after changing the driveshaft, the vibration is gone!!

 

[HerrStig]

There are often metal strips attached to the driveshaft for balance purposes. I don't know how every auto maker attaches them and how often they fall off but there are shops which specialize in driveshaft repair and balancing.

 

[Hokiefyd]

Thanks all.

Yes, the CR-V prop shaft uses staked-in universal joints. I have read about methods of replacing just the joints, but not in much depth. I'm not that far yet. I haven't heard of these systems being "picky" other than them getting little noisy on old fluid (which new fluid fixes). Fortunately, both ends of the prop shaft use 4-bolt flanges to attach to the PTO or differential; there is no fluid loss on either end with the prop shaft removed. This prop shaft has some balancing weights on both ends. They appear to be tack-welded into place. I have thought about taking the shaft to a driveline shop to have it balanced if I determine it to be the cause.

On the other hand, if I'm honest with myself, I use the AWD part of this car for fun only, and my other option would be leaving the prop shaft out, and even removing the differential and half shafts and just converting it to a FWD vehicle. The AWD versions of the CR-V have slightly better weight distribution and lower center of mass, but are also slightly heavier.

 

[SwampSurvivor]

If you remove the rear axle shafts make sure they aren't used to hold the wheel bearing together.

 

[Kiwi_ME]

If the frequency is in the audible range you might be able to identify it using an app on your smartphone like Speedy Spectrum.

I would be looking closely at the prop shaft's center bearing.

 

[Hokiefyd]

Originally Posted By: Kiwi_ME
I would be looking closely at the prop shaft's center bearing.


It seems to be perfect. It feels tight when I try to wiggle the prop shaft, and I have visibility on both sides of the bearing and there are no cracks in the rubber. The vibration does *feel* like a loose carrier bearing, though. I had that problem in a Nissan truck. I never fixed it, but it produced a similar vibration.

I plan to remove the prop shaft tonight and will update with what I find.

 

[Trav]

When i have a suspect Drive shaft issue i take the shaft and carrier bearing to a specialist. They redo the whole shaft from shot blasting it, epoxy coating, new joints and balance the whole assy.

On AWD that use a transfer case i take both shafts. Luckily we have one close by that is well known and does everything from over the road trucks to custom built shafts for racing or street rods and normal daily drivers.
I use these guys.

http://mitchelldifferential.com/

 

[threeputtpar]

I'd suggest marking the orientation of the driveshaft in the current position so you can get it back that way upon install.

 

[Hokiefyd]

Originally Posted By: threeputtpar
I'd suggest marking the orientation of the driveshaft in the current position so you can get it back that way upon install.


I will, thanks. I've already rotated it 180 degrees once, and I'm pretty sure it's slightly worse (which gives me encouragement that it really is something in the drive line).

 

[tdpark]

Hondas tend to be sensitivie to balancing so if you can - get the tires road forced balanced on a Hunter balancing machine. I have had similar problems on my Honda and when I got it rebalanced on a hunter machine- the vibration went away.

 

[Hokiefyd]

I removed the prop shaft last night. Certainly, all of the vibration that I introduced by flipping the rear flange and adding some hose clamps is gone. And I think that about half of the vibration in the mid-60s (mph) is gone as well. It's hard to tell; I think some of it is in the road that I normally drive at that speed.

One of the FCACs in town has a Hunter road force balancer, and I think my next step is trying that. I do think the prop shaft was contributing to some of the vibrations. I think some aspect is still there, though.

Interesting side note, and it could be placebo effect only, but the car feels lighter on its feet now, in terms of throttle response (from a stop). It seems easier to get up to speed, and in just the 20 miles I was driving last night and this morning, my average MPG meter has risen a few tenths. I will leave the prop shaft out for a while and see if my average mpg improves over many tanks.

 

[Trav]

Are you anywhere near these guys?

http://www.oliversdriveshaft.com/

 

[Hokiefyd]

I'm about three hours from Winston-Salem.

In your experience, what's a ballpark cost for balancing a two-piece driveshaft?

 

[SteveSRT8]

We have an excellent driveshaft shop locally.

Our HUGE extended van two piece shaft cost about 150 bucks to have removed, balanced, and reinstalled after u-joint replacement.

They should also check the yokes for mis alignment...

 

[Hokiefyd]

Thanks. I should also say that the u-joints on both ends felt a little gritty in all directions. If I re-install this prop shaft, I will install new u-joints.

 

[SwampSurvivor]

Do the U Joints normally do a lot of work? If the U Joints are feeling a bit gritty, then they very well could be causing the issue.

I've been chasing rear driveline vibrations on my Cherokee for 3 years now. Dropped well over $1000. Can't get rid of them. It's destined to drive at a max of 55 forever!

How is the AWD used for fun? To give it a bit more neutral handling?

 

[Trav]

I pay $70 for balancing only plus whatever joints are needed. I would guess in the $150 range as Steve said if it needs joints, more if it needs a center carrier.

It can make all the difference in the world to the smoothness of the vehicle.
Any sort of tight or roughness in the joint(s) or also binding in the splines of a two piece can cause vibration.

I would call them, see if they can refit the shaft after repair to drive home. The shop i use will, just have to make an appointment. Make a day of it and be done with it.