Community Forums

AFChap · 05-09-2021, 04:41 PM

I have a 2003 Winnebago Ultimate on a 2002 MM GT chassis. I had the aging air bags replaced in April as they were cracking. When I went to pickup the coach I noticed it was way to easy for me to get up onto the step with my new knees. When driving ,the suspension travel felt very short. Back to the shop ... very experienced diesel mechanic & his crew. They verified first that the correct airbags had been installed and the new bags appear to have plenty of inflation room available. When measured, the coach was 3-4 inches low compared to specs. They had difficulty getting Spartan tech support to respond by phone, but they were no help once they did. After working it for several days and replacing two equalizer valves they got it to within an inch of spec. The adjuster valve is set to max lift in the front. As I said, Spartan had no answer as to why it won't come up the other inch, just a "Well, that's pretty close." Has anyone encountered an issue like this with the front air bags?

Ray,IN · 05-09-2021, 08:56 PM

Assuming the correct air springs are installed, it sounds like the front ride height valve has been tinkered with. The distance between front shock mounting bolts should be 16+1/8".
reference: https://reycogranning.com/rg/wp-cont...-1320-1370.pdf (pg 20)

AFChap · 05-10-2021, 07:54 AM

Quote:

Originally Posted by Ray,IN

...it sounds like the front ride height valve has been tinkered with. The distance between front shock mounting bolts should be 16+1/8".

Indeed it has!! ... I could not find the right words when I made my original post, but "The adjuster valve is set to max lift" The most lift they can get out of it is 15".

rag_ftw · 05-10-2021, 08:07 AM

Certainly no expert here but are you sure they installed the correct bags?

Also I seem to recall a metal spacer plate that had to be fabricated for the bags to sit on when they replaced mine. Seems as though the original bags had the plate and the replacement bags didn't.

Maybe some of the more experienced guys will be along in a minute.

Ray,IN · 05-10-2021, 08:51 PM

Quote:

Originally Posted by rag_ftw

Certainly no expert here but are you sure they installed the correct bags?

Also I seem to recall a metal spacer plate that had to be fabricated for the bags to sit on when they replaced mine. Seems as though the original bags had the plate and the replacement bags didn't.

Maybe some of the more experienced guys will be along in a minute.

You are right, here is that thread: https://www.irv2.com/forums/f25/air-...nt-291945.html
After reading that thread again, I'm leaning more towards incorrect air springs are installed.

AFChap · 05-23-2021, 03:57 PM

Ray,

Thanks for that reference to the other thread. I will slip under the coach this afternoon or tomorrow and see what I see, support plate, bags sitting odd, etc. Also plan to contact Spartan to try to confirm the correct air bag part #s for my chassis.

AFChap · 05-23-2021, 05:32 PM

BINGO ... that thread has the answer I believe ... https://www.irv2.com/forums/f25/f25/...nt-291945.html

I rolled under my coach (rear first since it is higher off the ground) and the air bag bases are definitely metal ... good ring when I ding them.

But on the front, the air bag base is definitely NOT metal. Feels & sounds like plastic so must be the "fiberglass" version. Can't tell where it currently sits, but I can understand how that base could flex/bend over the sides of the support bracket and cause the airbags to "droop" and not reach sufficient height ... and eventually disintegrate. I will be on the phone first thing tomorrow to talk with my mechanic, and to schedule installation of some "support plates on the front."

Meanwhile, very glad we cancelled our 1200 mile round trip that was to begin last Thursday!!

Ray,IN · 05-23-2021, 09:07 PM

Best of luck Paul!

AFChap · 07-21-2021, 03:31 PM

And the saga continues ... but I think I have the answer. Got the plates fabbed & installed. Still 5/8" low. Doesn't sound like much but the suspension travel is a bit abrupt. Today, studying the hand full of invoices generated since March I suddenly realized the only place part #7593 is mentioned ... the correct front air bags ... is on an order sheet & on a return credit. AND, in addition to the correct rear air bag last number on an order invoice, buried in a list of parts is "Air spring-rear TE88139, 2ea". By process of elimination, in spite of verifying part numbers with me multiple times, they have to have installed these bags on the front of my coach!! Is it possible to read an air bag part number with the bag installed?

Ray,IN · 08-01-2021, 07:47 PM

Hi Paul, I've been busy elsewhere sorry I didn't get back.
This website indicates the ID number sticker is on top the air spring, then continues to explain how to find the ID by measuring the spring, hope it's useful: How to Identify an Air Spring or Air Bag Part Number - Stengel Bros Inc

This is the Firestone Engineering and design manual for air springs.https://www.firestoneip.com/content/...erial_2014.pdf Hopefully the measurements will also be helpful.

AFChap · 08-03-2021, 08:06 PM

I have concluded from my invoices, along with emails and conversation with the shop, that in spite of verifying part numbers with me numerous times, the shop "directly matched" the old rear air bags at a local vendor, thinking it was the old front air bag, and installing that rear bag on the front. It is NOT the correct rear bag either, but a pretty close match when I look at the specs of each. The shop is still trying to figure what happened and how it happened, telling me my coach must have had the wrong air bags on the front when I brought it in. At this point it is pretty clear to me what happened, but all I want to do is to get the right bags installed and then find a new shop to service my rig. This is not their first screw-up, but definitely the most expensive and drawn out ... this all started in March when I took the coach in for service and asked them to replace the 19 yr old air bags that were cracking. At least the correct bags got ordered today from Spartan.