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Air bag pressure in relation to weight


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So just throwing this out to get my brains warmed up and working. 
 

On my truck and 5vr combo, I have a set of bags on the rear of the rear of the truck to level it up when hooked to the trailer.

Now I cannot exceed 30 psi in the bags or it takes off to much weight and the truck gets squirley. 

Now on my Dip. I feel like the back axle is just dialed weight wise with all the gear loaded in. It has settled in and the weight is being carried great. 

The front however makes me feel like there is to much air in the bags. It’s not as glued to the road IMO. I cannot add weight to the front. 

So my question, are the bags designed to have say X amount of PSI in them based on axle weight? Or are they simply ride height or for comfort? 

I feel like I should be taking air out of the front bags, but I don’t have enough knowledge to understand it. 
 

As a side point, what’s the incl/decl switch on the dash? 
 

 

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8 hours ago, JDCrow said:

The front however makes me feel like there is to much air in the bags. It’s not as glued to the road IMO. I cannot add weight to the front. 

So my question, are the bags designed to have say X amount of PSI in them based on axle weight? Or are they simply ride height or for comfort? 

Sounds like you would be extremely thrilled after you install the Watts Link to your front end. Call Mike Hughes in California, here's the web site.

https://monacowatts.com/products.htm

The ride height control valve is designed to keep the coach level while driving and active regardless of the weight on each corner. The 8/10 bagger's are very stable. Try making a quick sudden lane change and see what happens. I had to one day while driving in Alaska towing a 30 foot cargo trailer when a moose decided to cross diagonally in front of us. Thankfully no one was coming from the other direction but then again this was Alaska way out in the boonies.

 

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On all the older Monaco Coaches with airbags the method used to control the air pressure in the airbags is controlled by the ride height valves on each axle. The air system will put whatever air pressure is necessary into the airbags to maintain the correct ride height as you travel.

It is very important that you maintain the correct ride height for you model coach.

How your weight is distributed plays a major roll in how the air bags manage the ride height. This is another reason to have your coach weighed on all corners to try and get as much weight evenly distributed over the axles for better handling.

The airbags will handle whatever air pressure you system operates on while traveling.

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Thanks everyone.

I have front watts installed, and it drives much nicer. Thinking of adding the cross bars to front as well. I just think it needs more weight on the front to be more “hunkered” or glued, but there is no way to add weight. (I’m at 8500 lbs)

I can say passing trucks are not felt. It’s a very nice feeling to not be pushed over. 

I also think there is play in my new TRW box. Based on what ones say here there should be zero. 

Little more work. Thanks again 

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You will not be able to add Cross bars to the Front on that Model coach. The generator location prohibits that installation. You can only add them to the rear and that will make a difference.

.

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39 minutes ago, David Pratt said:

You will not be able to add Cross bars to the Front on that Model coach. The generator location prohibits that installation. You can only add them to the rear and that will make a difference.

.

OK, I thought I read where Mike (seller) has them on the font of his coach, but I digress I don’t know his Gen set up. 
 

I have them on the rear. Love them. The rear of the coach feels solid. I have zero complaints with the rear. 

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 I was having the same problem with my 07 Dynasty I just added a little more pressure to the tag axle and it took the sway out of the front axle made it much more enjoyable to drive. I’m a retired truck driver so when I checked all the axle weights I found too much weight on my tag axle,  so I reduce the pressure on the tag And that made the front end  Squirrley  so I added 2 pounds back to the tag axle and everything smoothed out.

Don

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2 minutes ago, Donflem said:

 I was having the same problem with my 07 Dynasty I just added a little more pressure to the tag axle and it took the sway out of the front axle made it much more enjoyable to drive. I’m a retired truck driver so when I checked all the axle weights I found too much weight on my tag axle,  so I reduce the pressure on the tag And that made the front end  Squirrley  so I added 2 pounds back to the tag axle and everything smoothed out.

Don

Likewise I used to drive class 8 trucks (Dump, Belly, End, Chip) and had drop axles. So we could add/subtract air to move the weight around. If I felt steering (light) I’d lower the PSI in the drop axle. 
 

Coupled with my pickup thoughts, I didn’t know if either lowering the front PSI or raising the back PSI would shift more weight front to give me the feeling I’m after. 
 

I will day say now thinking about it, the rear is squatting more with the weight. Now I’m wondering if this is right height is not correct for the weight in the rear? 
 

Thanks again 

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Ride Height specs are based on each specific coach model not on the weight that it is or carrying.

Corner weights are the only true way to know what cold psi would be needed to carry that weight based on your tire size and model. I always add 5 psi to each tire over what the calculation determined as a safety factor.

My TPMS is set up to alarm me when it reaches the minimum psi not with the added 5 psi. That way I never go below what is required to carry the weight safely.

https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Brochure_ENG.pdf

Edited by Dr4Film
Added PDF file for determing corner weight psi
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1 hour ago, Dr4Film said:

Ride Height specs are based on each specific coach model not on the weight that it is or carrying.

Corner weights are the only true way to know what cold psi would be needed to carry that weight based on your tire size and model. I always add 5 psi to each tire over what the calculation determined as a safety factor.

My TPMS is set up to alarm me when it reaches the minimum psi not with the added 5 psi. That way I never go below what is required to carry the weight safely.

https://www.michelinb2b.com/wps/b2bcontent/PDF/RV_Brochure_ENG.pdf

I will corner weigh next time instead of axle weigh. 

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9 minutes ago, JDCrow said:

I will corner weigh next time instead of axle weigh. 

Axle weight is better than not knowing ANY weight however it doesn't tell you if one corner is significantly heavier than the opposite corner. That has been discovered by  a few members where one side is 500 lb's heavier than the opposite side. Plus it had nothing to do with storage weight  where you can shift that around but was attributed to slide weight. If one corner is heavier by a significant amount then the psi has to be calculated based on the heavier side. That's where axle weight only gives you part of the equation by taking the axle weight and dividing by two or four depending on the axle.

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32 minutes ago, Dr4Film said:

Axle weight is better than not knowing ANY weight however it doesn't tell you if one corner is significantly heavier than the opposite corner. That has been discovered by  a few members where one side is 500 lb's heavier than the opposite side. Plus it had nothing to do with storage weight  where you can shift that around but was attributed to slide weight. If one corner is heavier by a significant amount then the psi has to be calculated based on the heavier side. That's where axle weight only gives you part of the equation by taking the axle weight and dividing by two or four depending on the axle.

Well I can say, on the passenger side is the fridge, toilet, dresser, washer/dryer combo, all the batteries and inverter, propane tank, furnace, and I think the grey and black tanks are weighted to that side. I’d guarantee that it it heavier than the drivers side 

Edited by JDCrow
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Based on your signature you have a 34' coach.  The shorter coaches are light on the front because the engine overhang at the rear is the same for all coaches of the same model.  Thus, when you have a 40' coach there is more leverage on the front and additional weight on the front axle.  I  would recommend getting it weighted and moving as much forward as possible.  The ride height controls will set the pressure to maintain the ride height.  No other adjustments of air bag pressure is required.

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4 minutes ago, Larry Laursen said:

Based on your signature you have a 34' coach.  The shorter coaches are light on the front because the engine overhang at the rear is the same for all coaches of the same model.  Thus, when you have a 40' coach there is more leverage on the front and additional weight on the front axle.  I  would recommend getting it weighted and moving as much forward as possible.  The ride height controls will set the pressure to maintain the ride height.  No other adjustments of air bag pressure is required.

Yeah with the Shorty you loose a bay or two that is needed to add that weight. I only have 1 pass through.  The rest of the bays have coach operation stuff in them. 

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