Shes giving me not good vibrations

[Howmanygoes]

After a sounding board.

Truck developed a vibration around the time I fitted front bumper and winch. Can't see anything wrong or loose here. I also had the transmission fluid changed as I had a leak on the pan.

Vibration comes on about 50mph at 1800rpm then disappears about 60mph circa 2000rpm. No noticeable vibration at those revs stationary on the drive. Whilst driving I knocked into neutral and vibration was still there, though slightly less prevalent. No vibration through the steering wheel. Feel it most through the floor

I dropped out the rear prop and replaced the UJs and had it rebalanced. Still vibrating but a slight different one now, the prop balance was way out. I had the wheels balanced 3 of 5 balanced ok 2 didn't. 2 good ones on the front and the better 2 on the rear and the worst on the spare. I've now removed the front prop and replaced the UJs. This is going for balancing tomorrow. Also checked transmission mount whilst under there, looks good.

All 4 Wheel bearings were done less than 5k ago and had mot just before fitting of the bumper and transmission drain.

So if the balancing tomorrow doesn't work I've run out of ideas and open to suggestions.

 

[Jon Wildsmith]

Is the vibration still there if you drive it with each prop in turn removed?

 

[Howmanygoes]

@Jon Wildsmith that's a good idea. Haven't don't that yet. Whilst the front is out I will take it for a drive.

 

[Jon Wildsmith]

A wheel balance problem is usually more of a shaking feeling. UJ, prop balance, pinion bearing, or CV joint more of a vibration that goes through you and feel more terminal (especially prop related)! Not very scientific but the best way I can think to describe them! It's not uncommon to have changed a UJ / balance a prop and still have a problem, so if it hasn't gone with the front prop removed, try removing the rear again when the front is back and go for another drive would be my suggestion.

 

[clivehorridge]

This one may sound stupid and you haven’t mentioned handbrake, but… have you adjusted up the handbrake either at the shoes or the cable recently?
I ask, because every-time mine is adjusted (or maybe over adjusted on the tight side), the first 80 km gives my truck the shakes until the shoes have bedded to their new position.
Just a thought…

 

[flint]

If not already checked, prop shaft phasing might be worth a look.

 

[Howmanygoes]

Hi all. Prop in phase.

I did the handbrake a few months back now and was fine before the other works.

With front prop removed the vehicle will only move if the CDL is engaged. So not sure about running like that upto 60mph?

 

[Jon Wildsmith]

Yep, CDL needs to be engaged. Completely fine to drive at any speed like that but it will drive very differently as a 2wd!

 

[Howmanygoes]

Drive without front prop. Still vibrating and still all felt through floor/seat. Speed related and still between 50mph and 60mph.

Will put front diff back in and remove rear again and try that drive.

 

[Howmanygoes]

Removed rear prop and took it for a drive. Still vibrating. Supposed to be going away in less than 2 weeks sonwould be good to sort it before then.

 

[Jon Wildsmith]

I have spare set of wheels and tyres you can borrow to eliminate that, but they're in the midlands near J4a of the M5.

Did you adjust the front suspension after fitting the bumper and winch, so it's at a similar height to before? Wondering if CV angles changed significantly, but the vibration from those is quite mild unless seriously shagged.

Sounding like this could be a tricky one to track down. Do you get any sense of it being in front, right underneath, or behind you?

 

[Howmanygoes]

@Jon Wildsmith feels through the floor and seat. Not getting anything through the steering wheel.

Checked fluid levels and when warm the transmission fluid is a hair above the top marker.

Beginning to think transmission. Run up to speed until the vibration occured then turned off OD and it was still there. I am sure I can feel it through the hi low selector, but will double check this.

Going to go for another drive after lunch and check few other ideas.

Thanks for the wheel offer. I will bare that in mind.

 

[Jon Wildsmith]

You could put the gearbox in N, so you can shift the transfer into N, while the vibration is happening. Not ideal in terms of driving distraction, but might give further clues depending on if it has any effect or not. I believe H on the transfer has synchro, so you can re-engage H on the move, and then shift back into D to continue driving. Just don't try L on the move, pretty sure that doesn't have synchro and will grind.

I'm doubting it's your transmission as it otherwise drives ok(?) but the above will stop most of the transfer, and all of the main gearbox, rotating at road speed.

 

[frank rabbets]

I know Chris had a similar untrackable problem which he found by accident after a long time suffering. Very worn front dif pinion bearing. That would still be turning with prop shaft removed but obviously not under same load.

 

[frank rabbets]

Don't know re 100 props but I've seen 80 props "in" and "out" of phase with neither cars having vibrations so may be down to individual period/run design. Point is that your props should have been assembled identically to how they were without the vibration. Might be food for thought. Be very interesting to see what you find.

 

[Howmanygoes]

As an update. My truck is with Julian at OL crusiers. I hope its not gone there to die.

The rear off side wheel bearing was rotating in the hub and the nearside seal was for a second time passing. Had all of these replaced and if anything the vibration got worse, but the noise from the WBs has gone. Disconnected the rear prop again. Engaged CDL and still sounds bad.

Julian is going to start stripping back to try to rule out and localise the issue. My head says remove and check condition of the front diff and if gearing is fine rebuild with new seals and bearings.

Have a rear caliper that's binding (piston not slide) so will get that replaced too and perhaps coincidental that it's the same side as the leaking seal. That side does appear to get hot, smells it and faint smoking.

The team an OLC also think my rear prop is bent slightly, cant tellnon the bench only under rotation. Which is strange as I only recently (weeks and <250miles tarrmac) had new ujs and it balanced.

Now to get all this done I time for my ferry...

 

[Jon Wildsmith]

Fingers crossed Julian can get to the bottom of it for you then.