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Topic: Front Air Bag (Read 555 times) previous topic - next topic

Front Air Bag

I have my front Firestone air bags at the top of their travel to insert my stands to block the coach while I rebuild the 6-pack (my leak tester says the 6-pack is leaking).  The two bags on the passenger side and the rear bag on the driver side have extended to 13.25 inches.  The front bag on the driver side is only at 12.25 inches, one inch less.  This is after holding the front up arrow several times for a while and not seeing any noticable change of height

 Any ideas on what is going on?
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Front Air Bag

Reply #1 –

Assuming the bag itself is not leaking, maybe that is the valve that is leaking, or it's leaking faster than the others?

Re: Front Air Bag

Reply #2 –
No, quite likely nothing is wrong.  Remember in front only ONE ride height valve.  So left/right very rarely read the same dimension for ride height.

Quite possible the rear ride height was off left/right, throwing the front off side to side.
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: Front Air Bag

Reply #3 –
Thank you both, especailly Brett.  The leaking is causng the passenger side to sag, not the driver side.  So, I will not worry with this and proceed on the 6-pack rebuild.

FWIW,  I just opened the aux tank drain and got a shower.  Wish the air dryer on aux compressor worked better.  Plus I need to move the drain valves from the bottom of the brake and aux tank to the side of the coach so I can drain without having to be under the coach.
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Front Air Bag

Reply #4 –
 Wilkinson air dryer filled with 100% silica kitty litter works amazing . also  Brett is correct I have a 1 inch offset side to side 2002 U270 you can adjust the rear ride height valves to get a quarter offset
John Patrick
2002 U270

Re: Front Air Bag

Reply #5 –
John,  I see a number of Wilkinson dryers, several with the same cup as in your picture.  Could please share the model number?
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Front Air Bag

Reply #6 –
Unfortunately I am not near my motorhome at this time. I did at one time post the actual number.  I purchased off of eBay for $80
John Patrick
2002 U270

Re: Front Air Bag

Reply #7 –
Quote from: opelgt327 –
Unfortunately I am not near my motorhome at this time. I did at one time post the actual number.  I purchased off of eBay for $80
Wilkerson manual desiccant dryer
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Front Air Bag

Reply #8 –
Just by a strange chance, you don't have an odd ball shock under there that wont extend as far as your others? I just changed my front shocks, koni golds. It had a red koni and a yellow Monroe on it. I thought that was really strange. I put an adsp air drier on my coach a couple years ago. It seems to be doing its job, no tank moisture to speak of. Do a google of adsp air drier, I got mine in town at a big truck store.
92 Grand Villa
Silver 6v92
 side isle.
build# 3973

Re: Front Air Bag

Reply #9 –
Thanks Craneman.  Ebay, $99 open box with scratches.  ZORO, New $202.31

MT Ted,  My shocks are nearly new Koni Gold FSDs.  Thanks for the reply
Rudy Legett
2003 U320 4010 ISM 450 hp
2001 U320 4220 ISM 450 hp
1995 U320 M11 400 hp
1990 Granvilla 300 hp 3208T
Aqua Hot Service Houston and Southeast Texas

Re: Front Air Bag

Reply #10 –
Quote from: Rudy –
Thanks Craneman.  Ebay, $99 open box with scratches.  ZORO, New $202.31

MT Ted,  My shocks are nearly new Koni Gold FSDs.  Thanks for the reply
Also new with the silica from the same seller for 139.99

Wilkerson X03-02-000 Desiccant Air Dryer 1/4" NPT, with 15-960-000 Silica...
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean