Jump to content

Truck rear air leak


ruthanns1

Recommended Posts

Started having some leakage at the rear with my t2000 (truckers call this model Baboon butt) not long after we started the first trip. Kept hearing it leaking from the leveling valve behind the rear pig, so I replaced it. Years later now I still hold good air on the suspension. Those valves seem to start leaking around pivot shaft when they fail. Not a big job really, did it myself laying on the sand at Quartzite. You should check the air bag condition and their connections, not much on that part of the system to leak.

Yamaha V-Star
2007 Kenworth T2000 tandem aircutter
ThermoKing TriPack
2003 Holiday Rambler 36' Presidential
short trips-88 Allegro on Astro

Link to comment
Share on other sites

I wouldn't necessarily call it normal, but it is pretty common. I'm not sure if it would have been the case with your truck, but there were a lot of Volvos produced with a plastic leveling valve body that would develop cracks with age. That was the case with my truck when I bought it, and they were pretty significant cracks--the bags would totally deflate in an hour or so. After replacing the valve, I can go for several weeks at least before any noticeable drop in pressure.

45' 2004 Showhauler -- VNL300, ISX, FreedomLine -- RVnerds.com -- where I've started to write about what I'm up to

Headlight and Fog Light Upgrades http://deepspacelighting.com

Link to comment
Share on other sites

Ditto on the level valve. In 2007 I replaced the valve and all lines and fittings to original bags when I singled. The bags stayed up all the time. Even in winter parked for months. Last year down in Fl the bags would drop after a week or so, sometimes overnight. Valve was ok so went for the bags. They looked real bad..cracked etc but hard to see any leaks. Same time replaced the valve and lines etc and plumbed in ET hitch since I had the rear all open for hitch install. Has been solid since.

 

 

Bill and Joan and 3 Collie pups

2001 Volvo VNL 770 "The Doghouse" Singled short, "ET" hItch VED12 465HP Gen 1 Autoshift 3.58 ratio  2005 Mobile Suite 38RL3  2011 Smart Passion loaded piggybacK

Weigh-It Portable RV Scales http://www.weighitrv.com/

Link to comment
Share on other sites

Thanks Guys, I'll check all my air lines and the level arm. This weekend should be good weather and I can get under the truck.

I am so thankful that my wife stubble on this forum, you guys have been priceless.

 

Chip

Chip and Ruth

2000 Kenworth T2000 'Titus'

2006 Keystone Raptor 'Cletus'

2010 Smart 'Alyck'

Link to comment
Share on other sites

If the new valve mounts the same way, you shouldn't have to do anything special. At least on my truck, the rod that runs from the valve arm to the suspension is fixed with a screw at each end and not adjustable.

 

Of course, the new valve needed a new bracket, and I only learned that after driving ~100 miles back from the Volvo dealer. So I made my own from a sheet of aluminum, and positioned it so the valve arm was at the same angle as before relative to the valve body. That's been about 20,000 miles ago.

 

Just pay attention to which port is which on the valve--I remember a post some time ago where someone put the valve in backwards.

45' 2004 Showhauler -- VNL300, ISX, FreedomLine -- RVnerds.com -- where I've started to write about what I'm up to

Headlight and Fog Light Upgrades http://deepspacelighting.com

Link to comment
Share on other sites

Just thought of one more thing, mark the frame at the rear and measure the height with everything up and normal.

There is a golf tee sent to insert into the valve to center it, but in the end, you will want the frame to end up the original height.

There is a set screw to tighten the lever to the shaft. The reason for this is the drive shaft angle is real important and would be

changed if the leveling valve is not properly adjusted.

Yamaha V-Star
2007 Kenworth T2000 tandem aircutter
ThermoKing TriPack
2003 Holiday Rambler 36' Presidential
short trips-88 Allegro on Astro

Link to comment
Share on other sites

 

Just pay attention to which port is which on the valve--I remember a post some time ago where someone put the valve in backwards.

I did that when I converted my hitch to using leveling valve rather than gauge. :huh:

KW T-680, POPEMOBILE
Newmar X-Aire, VATICAN
Lots of old motorcycles, Moto Guzzi Griso and Spyder F3 currently in the front row
Young enough to play in the dirt as a retired farmer.
contact me at rickeieio1@comcast.net

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...