2018 1 Ton Dually Suspension Pulling 5th Wheel RV

Pulling our 5er in California Bay Area was BRUTAL! We felt beat to death by the time we arrived at our destination. I was very surprised at this given I have a new truck with airbags in the rear and a new Cedar Creek 42 foot RV with dual axles and the Dexter EX flex suspension and Trailair king pin hitch. Hoping there's someone out there who has experienced this and has resolved the issue. I'm not sure where to start. Should I upgrade the trailer suspension or the truck? Or maybe both???

 

Are you saying you have the RAM factory rear air suspension?

How much air pressure in rear tires? Should be 80 in front and not more than 65 in the rears. With that trailer you would most likely be fine with around 55 lbs inflation in the rears. None of the CC's are really pin heavy.

In you have 80 lbs inflation in the rear, that would explain a lot of your issues. SnoKing

 

Have you weighed out the truck and trailer, axle weights, and pin weight?

 

Yes! on the 1 ton dually the OEM is Airbags

 

What air pressure are you running in the air bags? What is the air pressure in your tires?

I am towing a 2016 34RL Cedar Creek with a 2500 Ram Mega Cab. The truck does have air bags that I installed for leveling purposes. These are inflated to 50 PSI. I also have Nitto Dural Grappler Tires on my truck, LT285/70R/17 126R which are rated for 3750 @ 80PSI. I run the front tires at 50 PSI and the rear tires at 70 PSI which is more then enough to support the load and provide a comfortable ride.

I would also weigh the truck and camper across a CAT scale to know what your weights are. You can adjust the tire pressure accordingly to the scale weight and air bag pressure. This will should improve your ride.

 

Yes...

 

Tire pressure is 80 in the front and 65 in the back

 

So with 7300 weight on the rear axle, you are running pretty light. Is this a CC 38FLX? At 25,420 combined you most likely do not have that much stuff loaded in the trailer at this point.

50 lbs inflation in a LT235/80R17E is good for 2040 lbs load, or 8160 for the rear axle. At 55 they are good for 2190 or 8760 for the rear axle.

 

OP has the close system OEM factory rear air suspension, not air bags.

 

I drive from WA thru the Bay Area, and then on to FL at least once a year, with my 5th wheel. The area you are writing about is one of the worst sections of road in the US. Another really bad area is I-10 near the LA-TX border. I am constantly looking in my rear mirrors to see if the tires and axles are still on the rig, when going thru those areas. Sounds like you have a good setup, so I wouldn't change anything (maybe air pressure), but try to slow down. Often there is just no way to avoid those bad areas, so the only thing you can do is slow down and try to avoid the bigger pot holes.

 

I have the same factory rear air ride, I love it!!!

I would drop rears to 50psi. Be sure to run the suspension in Alt Ride Ht Mode.

 

DANG!! I'm going up to Concord,ca next month and was going to use Hwy 99 to hwy 12 and sneak in the back door so to speak.. What roads up there are REALLY bad? Off topic a bit but curious..

 

Much of Hwy 99 has been improved thru Modesto and Manteca area.
Slow drive thru Lodi downtown before once again on Hwy 12 proper after crossing I-5 intersection.
Construction on Hwy 12 for about 5 miles. New road and wall but 45 mph speed limit.
Left on 160 otherwise you cross over river into into Rio Vista.
Road ok but a little bumpy at times.
Cross Antioch bridge and back on Hwy 4. Good road but people drive like crazy fast...75-80 not uncommon in 65 zone.

Hope this helps.

Charlie

 

The coach is a CC 38EL

 

Alt Ride Ht Mode? Why not the Trailer Height option?

 

"Alt Trailer Ht"

#ad

 

Here is a tire pressure chart. Based on your actual load I would run 45 rears. That will give you 8,220# capacity.

#ad

 

You read the chart wrong. That is for single use. For dual tires 45 lbs inflation is 7480 capacity. Snoking

 

I always figured the OEM and Tire Manufacturers know a lot more about why they recommend certain tire pressures than anyone else and they placed that label on your trucks doorjam for a reason.

what some tire manufacturers have to say about the subject

http://us.coopertire.com/CooperTiresConsumer2013/media/Documents/Service_Bulletin_105.pdf

https://www.toyotires.com/media/1496/tsd-12-013_rv_motorhome_tire_inflation_safety_maintenance_0.pdf

https://www.goodyearrvtires.com/tire-inflation-loading.aspx

 

Yep, the inflation number on the placard for each axle are for the maximum rated load for each individual axle. Our 2001.5 manual actually had a chart showing reduced pressures for lighter loads.

My 2015 manual has some statements:

•Improperly inflated tires are dangerous and can cause collisions. •Under-inflation increases tire flexing and can result in over-heating and tire failure.
•Over-inflation reduces a tire’s ability to cushion shock. Objects on the road and chuckholes can cause damage that result in tire failure.
•Over-inflated or under-inflated tires can affect vehicle handling and can fail suddenly, resulting in loss of vehicle control. •Unequal tire pressures can cause steering problems. You could lose control of your vehicle.

+++


Inflation pressures specified on the placard are always “cold tire inflation pressure.” Cold tire inflation pressure is defined as the tire pressure after the vehicle has not been driven for at least three hours, or driven less than 1 mile (1.6 km) after a three hour period. The cold tire inflation pressure must not exceed the maximum inflation pressure molded into the tire sidewall.

+++

SUPPLEMENTAL TIRE PRESSURE INFORMATION — IF EQUIPPED A light load vehicle condition is defined as two passengers [150 lbs (68 kg) each] plus 200 lbs (91 kg) of cargo. Cold tire inflation pressures for a lightly loaded vehicle will be found on the face of the driver’s door.

+++

Inflation Pressure This is the cold tire inflation pressure for your vehicle for all loading conditions up to full GAWR.

The one above is a result of the Ford/Firestone tire issue and lawyers. Now the manufacture wants you to run around with over inflated tires for the load one in hauling. A little common sense and knowledge of your load is required now.

They acknowledge over inflation can adversely effect handling, yet do not actually tell you to reduce pressures when running lightly loaded.

When I put new tires on the 2015, Costco refused to put reduce pressure in my rear tires. We now live in a nanny state!

SnoKing