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Test Drive Coach Without Front Shocks?

There's a heck of a loud noise coming from the front-end of our FT whenever encountering road surface irregularities.  I feel nothing
unusual in the steering and it almost sounds like a shock absorber is loose.  Last fall I replaced all the air bags and in doing so I R&R'd
all the shocks, noting nothing unsusual in mounting or dampening action.  I also replaced the entry steps at about the same time, and shortly after that we headed to Florida.  I heard the noise almost immediately at slow speeds so I pulled over in a church parking lot to
make sure the front wheels and tires weren't loose.  Once I determined the lug nuts were tight I headed south.

We stopped in Tampa to see Red Tractor and took the coach for a test drive with him behind the wheel, but after driving it and looking at the front-end from underneath he too was baffled.  Stepping on the service brakes did nothing to resolve the noise so we
were confident that it wasn't a brake caliper.  I wiggled the new entry steps and didn't think that was the sound we were hearing.  The noise seems to subside at higher speeds, which sounds crazy I know.

Last week I did a brake job, cleaned the slide pins, adjusted the slack adjusters and lubed/purged the calipers.  Today I took it for a test ride with a friend and had high hopes of finding the source of the noise, but we really haven't made any progress.  We did however remove all four of the Bilstein shocks, and looked at everything closely, including mounting holes, bushings and nuts and bolts.  Nothing seems out of the ordinary, so I'm wondering if I can do any harm to the new air bags if I take a test drive without the shocks to see if the noise went away.  I have studied the front end but don't see what limits the upward travel of the coach itself when going over a whoop-de-do, but can't believe the shocks are the limiters.

Can I test drive the coach with no front shocks and not do damage to the air bags?  Also, does anyone know the torque requirements for the eight nuts/bolts that secure the straight axle?







Re: Test Drive Coach Without Front Shocks?

Reply #1
See if the grommets are worn at the mounts where the shocks are.. Mine has a thunk under the radiator area for the generator.. havnt located what it is yet but I think the radiator moves on the larger bumps.

Re: Test Drive Coach Without Front Shocks?

Reply #2
1.  I have studied the front end but don't see what limits the upward travel of the coach itself when going over a whoop-de-do...

2.  Can I test drive the coach with no front shocks and not do damage to the air bags?

3.  Also, does anyone know the torque requirements for the eight nuts/bolts that secure the straight axle?
1.  I'm pretty sure it's not the shocks (assuming they are the correct length).  They would not last long if that was the case.  I don't think it is the air bags...  It should be easy to figure it out, however.  Just go out and use the "RAISE" button on HWH panel to lift your coach to upper limit.    Insert front safety stands.  The crawl under the front and see where the "mechanical stop" actually is.  I suspect there will be a little metal "pad" of some kind between the suspension members at that point, wherever it is.

2.  I would guess the answer is "Yes", but I will let you test my supposition on your coach.

3.  Sorry, no idea.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Test Drive Coach Without Front Shocks?

Reply #3
#3  Those should be 3/4" fine thread grade 8 ~300 FP

Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Test Drive Coach Without Front Shocks?

Reply #4
 Of course you can test it . Drive it slow  without bottoming.
  The panhard bar may be a touch loose and make some noise.  Paint the axle/trailing link area  and watch for tracks. 
 All of the  axle ,trailing arm 3/4 bolts are 250+ tq.  The shock bolts are 200ish and the air bags are 20ish . 

Re: Test Drive Coach Without Front Shocks?

Reply #5
There's a heck of a loud noise coming from the front-end of our FT whenever encountering road surface irregularities.  I feel nothing
unusual in the steering and it almost sounds like a shock absorber is loose.  Last fall I replaced all the air bags and in doing so I R&R'd
all the shocks, noting nothing unsusual in mounting or dampening action.  I also replaced the entry steps at about the same time, and shortly after that we headed to Florida.  I heard the noise almost immediately at slow speeds so I pulled over in a church parking lot to
make sure the front wheels and tires weren't loose.  Once I determined the lug nuts were tight I headed south.

We stopped in Tampa to see Red Tractor and took the coach for a test drive with him behind the wheel, but after driving it and looking at the front-end from underneath he too was baffled.  Stepping on the service brakes did nothing to resolve the noise so we
were confident that it wasn't a brake caliper.  I wiggled the new entry steps and didn't think that was the sound we were hearing.  The noise seems to subside at higher speeds, which sounds crazy I know.

Last week I did a brake job, cleaned the slide pins, adjusted the slack adjusters and lubed/purged the calipers.  Today I took it for a test ride with a friend and had high hopes of finding the source of the noise, but we really haven't made any progress.  We did however remove all four of the Bilstein shocks, and looked at everything closely, including mounting holes, bushings and nuts and bolts.  Nothing seems out of the ordinary, so I'm wondering if I can do any harm to the new air bags if I take a test drive without the shocks to see if the noise went away.  I have studied the front end but don't see what limits the upward travel of the coach itself when going over a whoop-de-do, but can't believe the shocks are the limiters.

Can I test drive the coach with no front shocks and not do damage to the air bags?  Also, does anyone know the torque requirements for the eight nuts/bolts that secure the straight axle?







I had the same problem, removed the steps. screen door, and tightened down every nut and bolt in the front end, and shock mounts and bolts and nuts, also checked brake calipers and slide pins. Finally gave up and took  coach to Keith R. at MOT. After 1 min test drive, he said a shock loose. Turns out one of the upper mount nuts was not completely snugged. [ the ones you cannot really see. ] My wimpy battery impact did not tighten it up when I installed my new FSD's. His air impact did the job. MOT only charged me 1/2 hour labor for the whole thing. [Did pay $200 for fuel to get up to Nac. and back.]
 
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Test Drive Coach Without Front Shocks?

Reply #6
Grab and or take a pry bar and see if the torque rods have any play,if they do the bushings are worn.
On the shocks,if they are the original ones I would replace them,I did the same thing with my old shocks,took one off and it
seemed to have dampening and was not loose but when I changed them it made a night and day difference.
If indeed it is a loose nut and bolt get some new nuts,forgot the name but those nuts with the plastic thread tightening are
a one time use and alot of bigger engines use them and they recommend replacing if you take them off,you would only need 4.
96 U270 BUILD 4810
85 380SL
Drummonds TN.


Re: Test Drive Coach Without Front Shocks?

Reply #8
No firsthand knowledge of it, but I don't think I would drive it without shocks on. Asking a lot of the airbags maybe? Taking a critical piece of the suspension system out to check for noise doesn't seem to be the right thing to do. I would check what Jim C said first and  use the Nylocks like John and T-Man suggested. See it that helps.
I have this strange noise when I drive as well.... up above. Couldn't figure out what in the heck is was, sounded like a spring being sprung over and over... Till I remembered the ant ears the previous owner put in for cellular reception... they must  move around a bit in the slipstream and go bong over and over, right over our heads. Plan is to relocated them at some point. Its pretty annoying.
Bob
'99 U320 40 WTFE
Build #5462,
1500 Watts Solar 600 amp Victron lithium
2012 Jeep Grand Cherokee Overland Hemi
Instagram bobfnbw
Retired

Re: Test Drive Coach Without Front Shocks?

Reply #9
As long as you have a route without a lot of bumps that would elicit much suspension travel, no problem driving without shocks.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Test Drive Coach Without Front Shocks?

Reply #10
I beleive he would need the bumps to find the issue he is investigating.. Would not recommend bags only


Re: Test Drive Coach Without Front Shocks?

Reply #12
First hand experience:

Yes, you have to moderate speed and route so you have some suspension travel, but not too much.

I have driven coaches on short drives with no shocks on the front-- last one because owner (Happened to be a Safari, not Foretravel, but diagnostics the same) swore that his shocks were causing a rough ride.  I removed the shocks (did not tell the owner what change I was making) and we went for a (yes, careful) drive.  Same rough ride.  When we got back, I showed him his shocks sitting on the work bench-- clearly not the cause of the rough ride.

Yes, weighted axles (front seriously under loaded-- an issue with a number of Safari coaches)-- he moved a bunch of weight forward and then adjusted tire pressure to that recommended for his actual weight.  Old shocks reinstalled-- ride materially improved.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Test Drive Coach Without Front Shocks?

Reply #13
I don't see anything limiting lateral movement other than the 4-link itself.


Hopefully, someone can post a picture.  I assume you have the solid front axle, not IFS.

The panhard rod/track bar goes from axle on passenger's side to body on driver's side. Yes, transverse to the long axis of the coach.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Test Drive Coach Without Front Shocks?

Reply #14
Yes, solid axle.  I see only 4-bars and one other adjustable bar that's about two feet long and sits above the axle maybe a foot.  It's transverse and is bolted to mounting plates directly over the axle mounting bolts............but that doesn't tie the chassis to the body.  I have panhard bars both front and rear on my Model A but I'm not seeing that application on the FT.

Re: Test Drive Coach Without Front Shocks?

Reply #15
T-Man,
From your first post I would say to look closely at what was worked on prior to noise. 
In my past life I would read the write up then I would pull the file to see what was last worked on and start my search in that area.
Keep us posted on your findings.
Jerry & Nanci
1999 U270 34'WTFI
2011 Malibu
A smart man knows what to say, a wise man knows when to say it.

Re: Test Drive Coach Without Front Shocks?

Reply #16
T-Man,
From your first post I would say to look closely at what was worked on prior to noise. 
In my past life I would read the write up then I would pull the file to see what was last worked on and start my search in that area.
Keep us posted on your findings.

Thanks Green99. 
Bought our first "coach" in Douglasville years ago at John Bleakley's.

Re: Test Drive Coach Without Front Shocks?

Reply #17
Yes, solid axle.  I see only 4-bars and one other adjustable bar that's about two feet long and sits above the axle maybe a foot.  It's transverse and is bolted to mounting plates directly over the axle mounting bolts............but that doesn't tie the chassis to the body.  I have panhard bars both front and rear on my Model A but I'm not seeing that application on the FT.

Upon closer inspection from the passenger side I see now that the transverse bar between the two air tanks is indeed the panhard bar.

Re: Test Drive Coach Without Front Shocks?

Reply #18
Update:

I did a brake job while installing helper springs on the calipers, removed the four front shocks and replaced them with Koni FSDs,
torqued the shock mounting bolts/nuts nice and snug with my new HF Earthquake impact wrench and finally went for a test drive today.  After checking things out I believe that one of the top mounting bolts wasn't tight enough because of galling so I replaced all the bolts and nuts to give the Earthquake it's best chance at tightening.   

Wow, what a difference the new shocks that are mounted properly make. The FT is now really quiet and fun to drive!!
The new Konis are really a great ride improvement.  Unbelievable!

Thanks to everyone for their input, especially JCUS for the shock mount diagnosis, and BBEANE for his help with lubing and purging
the calipers and adjusting the slack adjusters.


Re: Test Drive Coach Without Front Shocks?

Reply #19
Would get the rear as soon as you can.
96 U270 BUILD 4810
85 380SL
Drummonds TN.