Community Forums

bouvier · 12-02-2018, 11:28 AM

Hello & Happy Holidays
I have a1999 forest river 32 ft. class A coach. Lately I have been feeling a vibration when I am giving gas, it goes away when I leave off the gas.
It seems worse when the cruise control is on. It also seems to be getting worse
the more I drive. The U joints feel ok, but I haven't replaced them.
Any suggestions would be appreciated.

Thanks

Pat

FIRE UP · 12-02-2018, 11:57 AM

Quote:

Originally Posted by bouvier

Hello & Happy Holidays
I have a1999 forest river 32 ft. class A coach. Lately I have been feeling a vibration when I am giving gas, it goes away when I leave off the gas.
It seems worse when the cruise control is on. It also seems to be getting worse
the more I drive. The U joints feel ok, but I haven't replaced them.
Any suggestions would be appreciated.

Thanks

Pat

Pat,
A few things to maybe take a look at.
1. Motor mounts, while not normally an issue, one never knows, worth a check
2. Transmission mount, same, worth a look
3. Center support bearing for the drive shaft. Normally encased in a rubber boot, it can wear to the point it doesn't support the joint between the two (or more) drive shafts.
4. U-joints. I know you said the "feel" ok but, you need to make sure there's no tension on them when you do your checks. Make sure the wheels are blocked and the coach is in NEUTRAL and the parking brake off. Yes I know, the safety police go nuts on this sort of thing but, if the wheels are chocked/blocked, the coach ain't going anywhere and the drive shaft(s) have no tension on them which, will reveal ANY play in the u-joints IF there is any.

Normally, components in engine operation don't produce any vibration but, again, when ruling out all other potential causes, might be worth a look.
Scott

twinboat · 12-02-2018, 12:42 PM

Look for rust around the U joint caps, sign of seized U joint.

Check slip joint for excessive play, the blue plastic coating may be gone.

Check the hanger bearing. Is sits in a rubber doughnut. When it fails, it melts the doughnut.

All checks should be done with wheels chocked and parking brake off while in neutral.

Waiter21 · 12-02-2018, 02:19 PM

If you have a Ford F53. Ford issued TSB for vibration. You can read about it here:

Funny vibration around 50 mph – Wheel Centering on F53 – 1999 Southwind 35S

..

jackreno · 12-02-2018, 04:16 PM

MY 08 Bounder on a 07 F-53 chassis also had vibrations, I have 19.5 rims and have tried everything, new tires, centramatic balancers, front end aligned, swap tires around on motorhome and nothing worked, so I bought 6 new 19.5 rims from Accuride and bought 6 new Firestone FS561 tires and all hunter balanced and now my ride is perfect, no more vibrations, bounce, shakes and so forth.

Those old 19.5 rims on the F-53 were made bad and wont center on the hubs.

Soppy · 12-02-2018, 04:36 PM

It could be the U joints or hanger bearing. The U joints might feel tight, but there could be internal ware that will cause a vibration. A seized U joint will also cause vibration. The one at the diff is normally the first one to go as it the one with the steepest angle and gets the most dirt and water on it from the road.

Dav L · 12-02-2018, 05:53 PM

If the vibration is only while accelerating, then more likely driveline related than wheel balance / centering related.

Mojim · 12-03-2018, 08:18 AM

I had same thing F53 with V 10 turned out to be ign coil ...that's right

MSHappyCampers · 12-03-2018, 08:27 AM

Hi Pat!

Welcome to IRV2! We're sure glad you joined the gang!

I would suspect the u-joints but then I'm not a mechanic. Just noticed you are kinda new on IRV2 and wanted to say hello! Have fun and keep her between the ditches!

Good luck, happy trails, and God bless!

nathaniel · 12-03-2018, 10:01 AM

Quote:

Originally Posted by grumpyman

I had same thing F53 with V 10 turned out to be ign coil ...that's right

i had the same issue with a ford truck, vibration when accelerating and in overdrive. turned out to be a coil pack. set the cruse and it would shake the whole truck. turn overdrive off and it smoothed out. thought it was the transmission but turned out to be a individual coil pack.