Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: sedelange on August 09, 2019, 10:58:15 pm

Title: Ride quality
Post by: sedelange on August 09, 2019, 10:58:15 pm
The quality of the ride in our 2005 U320 seems to have steadily gotten worse in the last year.  At first I attributed it to the worsening roads, but now I am on I10 around Van Horn and the road appears smooth but not the ride. Small vibrations are constant and any large dips or bumps will make the bus move up and down about 3 cycles.  I am also experiencing one or more rattles in the front suspension.  While not loud, the rattle is noticeable.  We currently have 85,000 miles on our coach with about 45,000 on Koni FSD shocks. To me it seems a little early to need to replace shocks and I would think the torque tube bushings should last longer than 85,000 miles. Any suggestions?
Title: Re: Ride quality
Post by: Pierce & Gaylie Stewart on August 09, 2019, 11:28:38 pm
Sounds like it may be your shocks. Have you taken a look at them? Check the shock bushings, check for leaks, shock mounts. If your a DIYer, pull the bottom loose and see how effective they are and if both are the same. Three cycles reminds me of "50's Detroit iron where the shocks were gone in 20K. Normally, Koni or Bilstein shocks last a long time, perhaps several hundred thousand miles.

Pierce
Title: Re: Ride quality
Post by: Twig on August 10, 2019, 12:18:14 am
Which way you headed? I'm in Deming, NM.
Title: Re: Ride quality
Post by: sedelange on August 10, 2019, 06:12:22 am
The more I read online, it's not that uncommon for Koni's to fail that early.  Looks like I get to replace them when we get back to Houston.
Title: Re: Ride quality
Post by: John S on August 10, 2019, 06:57:14 am
I replaced my Konis at about 80k miles
Title: Re: Ride quality
Post by: John44 on August 10, 2019, 06:59:02 am
Would think that as many of us that have the Konis this would have come up before,is your air pressure good?The bushings would
cause more of a wander.Try doing what Pierce said with one shock and see how it feels.
Title: Re: Ride quality
Post by: Travelin' Man (RIP) on August 10, 2019, 08:37:58 am
The first thing I would do is make sure the bolts/nuts that hold the shocks top/bottom are tight, and I mean real tight ................ like impact wrench tight.
Title: Re: Ride quality
Post by: Pierce & Gaylie Stewart on August 10, 2019, 10:13:45 am
If the shock bushings are shot, that could be the reason for the noise also. A friend just had to replace the rubbers in his Toyota 4x4 as they were making noise. Shocks were good, just the rubber bushings. 110,000 on our U300, 240,000 on our RAV4 and 440,000 on MBZ 300SD, 190,000 on ML320 on still excellent OEM shocks on all of them. Gas filled shocks may seep a little but be OK. Pull the bottom to the side and test them. A sure way to tell if one or both have gone south.

Pierce
Title: Re: Ride quality
Post by: gracerace on August 10, 2019, 10:45:41 am
What Travelin' Man said.
Went through that too. I replaced the bolts to be safe.
I used a breaker bar to tighten them.
Chris
Title: Re: Ride quality
Post by: Caflashbob on August 10, 2019, 12:07:12 pm
If memory serves me the Koni FSD shocks, if registered with them, had a guarantee

From KONI NA site

FSD
Excellent ride quality on all road surfaces
Improved control
Reduced road noise
Gold metallic finish shocks
Less expensive than electronic systems
Limited Lifetime Warranty
Title: Re: Ride quality
Post by: sedelange on August 10, 2019, 12:57:57 pm
Been observing this liquid filled toy sitting on dash. It vibrates at about 10hz.  If I calculate correctly that is about what the tires rotate. Obviously I could have lost a wheel weight, but it's not that out of balance, just a constant vibration.
Title: Re: Ride quality
Post by: John44 on August 10, 2019, 01:51:10 pm
Have the beads put in or the centremic devices.
Title: Re: Ride quality
Post by: Caflashbob on August 10, 2019, 02:00:53 pm
Centrimatics was my choice
Title: Re: Ride quality
Post by: sedelange on August 10, 2019, 03:28:54 pm
After a couple of hours watching the toy shake, I notice the vibration has a harmonic of about 30 seconds.  Calculating the tire diameter and speed, it appears one tire is 0.067" smaller in diameter.  The vibration is not that large, it's just consistent. Apparently the shocks aren't dampening out the 10hz vibration of the tires. I am scheduled to have the engine serviced Tuesday and they are going to check the shocks.  After that I am having the tires removed and checked just to see how far off they are.  Looking at adding Centramatics, but I want to see how far off the tires are (too curious).
Title: Re: Ride quality
Post by: ohsonew on August 11, 2019, 07:49:34 am
Centramatics made a huge difference in a smooth ride. My coach is smoother than my 2 Buicks now, before, not so much.

Larry