Tag axle

[KevinH]

Two years ago I went to a reputable caterpillar dealer. They did a full service oil, fuel, Hydraulic, coolant, and general inspection. When I got home after picking it up i back in my driveway I hit the tag button to raise the tag and the tag would not go up. I called the caterpillar dealer and they said they did nothing with the tag in the work that they did. Couple weeks later the tag axle started working. Last year I had a different mechanic do the same service got home tag axle worked. Went to the caterpillar dealer this year same service got home the tag axle‘s not working. I haven’t called them because they’re probably gonna tell me the same thing they told me last time. Any ideas what could be causing this. C13

[DavidL]

The time to diagnose is when it's not working.

Because if it is working then a Wiggle Jiggle test is about what one can do.

Sounds like loose electrical connection.

 

[vito.a]

The Monaco tag axle lift system uses pneumatic pistons to raise the tag while simultaneously deflating the air bags.  Usually it will not lift completely, but just skim the ground. 

Your 2006 coach will have an HWH air ride system.  In 2007 they went to the Valid air system.  

Some good reading:

2004 Monaco Executive Tag Axle - iRV2 Forums

Monaco tag axle lift - iRV2 Forums

[96 EVO]

17 minutes ago, vito.a said:

The Monaco tag axle lift system uses pneumatic pistons to raise the tag while simultaneously deflating the air bags.  

My tag axle is raised by a pair of small air bags.

[Ivylog]

On 4/18/2022 at 9:51 PM, 96 EVO said:

My tag axle is raised by a pair of small air bags.

Actually it’s a Type 30 brake chamber.

[Frank McElroy]

Dick - Thanks for that info.  I thought those looked like a brake chamber and now I know. 

On some coaches Monaco included them to actually lift the tag off the ground but on long models with heavy engines like the ISX, the tag axle is not lifted, just the air is dumped from the tag air bags. 

On coaches with engine like mine with the ISL, to have the tag actually lift off the ground, it is important that the drive axle ride height be set correctly.  On coaches designed to lift the tag, if the drive axle ride height is set too low, the tag won't lift off the ground. 

[KevinH]

Thanks for all the info. I haven’t had a lot of time to figure out what’s wrong. I was hoping it was just gonna start working again like I did last time. If I figure out what it is I will post on here what the problem was. I don’t use it very often only when backing in on asphalt or concrete in a tight situation

[Ivylog]

Frank’s rarely wrong BUT my 08 45’ Navigator has the chambers that push on a arm that pull the chains for lifting the tag. Yes, if the chain is adjusted to long, it will not lift the tag.

Even the 09 Signature with the uprated 15K hitch has the lifting mechanism BUT you are warned to not use it if you have a heavy trailer connected… you could be overloading the drive axle by 50%. “15,000 Lb. Hitch with Non-Liftable Tag When Tow Vehicle Is Hooked up” Also it has “Rear Tires: 295/80R/22.5 Front Tires: 315/80R/22.”

When I first had a tag, I would lift it if I was making multiple turns. Between tires aging out and it not making much difference in turning radius, I haven’t lifted my tags in 15+ years. OK I have to replace the tag tires.

Edited April 22, 2022 by Ivylog

[Hypoxia]

My '07 Signature with the ISX, the tag lifts off the ground.   The Valid book says the drive air springs get air added for 10 seconds to make up for the added weight.  Using the tag lift is a slow process since they are fed by 1/4" air lines.  It sure helps getting in tight spaces or turning around.  I find myself using it more & more but have to be careful since the oil pan does get closer to the ground.

I also use the tag lift to help climb on to levelling blocks one place we park that is on a slope.

Tag Axle Lift Operation.pdf

[Ivylog]

53 minutes ago, KevinH said:

Thanks for all the info. I haven’t had a lot of time to figure out what’s wrong. I was hoping it was just gonna start working again like I did last time. 

My educated guess is it’s an intermittent electrical issue. Maybe, in servicing the engine, a wiring harness is moved (reaching into the engine on driver’s side) causing the problem.

[Frank McElroy]

17 minutes ago, Hypoxia said:

My '07 Signature with the ISX, the tag lifts off the ground.   The Valid book says the drive air springs get air added for 10 seconds to make up for the added weight.  Using the tag lift is a slow process since they are fed by 1/4" air lines.  It sure helps getting in tight spaces or turning around.  I find myself using it more & more but have to be careful since the oil pan does get closer to the ground.

I also use the tag lift to help climb on to levelling blocks one place we park that is on a slope.

Tag Axle Lift Operation.pdf 618.25 kB · 1 download

Thanks for the correction.  Somewhere I thought that the heavy engine coaches didn't have the option to lift the tag.  Nope, as it turns out even heavy coaches have that option - good to know.