Pumping up your RV dualie tires

[DaveMcArthur]

Hi!
We've had a Coachmen Beyond 2021 for about a year and are still learning how to maintain and use it. Lots of fun! One seemingly simple issue is how to fill its tires. Our experience may not be like yours and you may have solved this problem in a different way (which we'd be interested in hearing), but...

Gas station and home plug-in tire inflators can do just fine with most RV tires – except inner-dualie tires. The problem is that you need an inflator hose that is long enough and flexible enough to reach the inner-dualie valve. The hose also needs to attach by screwing onto the valve – we found that hoses that attach through tightening a lever simply can't get into the tight space between the outer- and inner-dualie tires.

We tried unsuccessfully to get several inflators to work on our Coachman 2021 Beyond (with a Ford Transit chassis). The Slime 40047 inflator was the first one we found that would work for us. We are now able to fill all of our tires to their specified pressure levels. This is a big relief because – as you may have discovered yourself – you cannot go into any local garage, or even, in our case, a Ford repair center, and expect them to be able to properly inflate your inner-dualie tires. If you have had this sort of unhappy experience, we recommend you try out the Slime 40047.

While the Slime 40047 works well for us, it is not a magic bullet. It still takes time and care to attach the hose to the dualie tire valve. Because it is awkward to thread the hose on and remove it when done, you can easily lose several pounds of pressure. We therefore tend to overfill our inner-dualie tires to about 60 lb (the ideal pressure is 55 lb) and, if we are lucky enough to unscrew the hose without losing much pressure, we manually release as much air as we need to.

If your inner-dualie valves are aligned well with the holes in the rim of the outer dualie, attaching the inflator hose to the inner dualie should be easy, On the other hand, if they are not well aligned, attaching the hose can be very challenging. If this is the case with your dualie tires, you may need to get your mechanic to reposition your outer tires to get the valves properly aligned. Good luck with that!

[avanti]

Getting valve extensions for the inner tires is money well-spent. Just make sure they are of the all metal type. Never, ever consider the rubber ones.

[@Michael]

Originally Posted by avanti

Getting valve extensions for the inner tires is money well-spent. Just make sure they are of the all metal type. Never, ever consider the rubber ones.

Yep.

My 2019 Beyond (Crossfit) came with extended brass valve stems that are long enough and angled outward. As long as the outer wheel is rotated correctly, it's accessible with either a regular chuck or the trucker style extended chuck.

Coachman must have done something different in 2021?

[BikerMonkey]

I found this on Amazon... WYNNsky Tire Inflator with Tire Pressure Gauge, Extended Straight-on Air Chuck with 12 Inch Rubber Air Hose

You can also get another straight on brass extender


Haven't tried either, might work?

[WillieJ]

Milton makes quality inflators, gauges, etc. You can find this one other places for much less than the price on the Milton site:

https://www.miltonindustries.com/dua...inflator-gauge. The chuck grips the valve stem, making inflation easier.

About 50 bucks on Amazon and other vendors.

Important to keep duals inflated to the same pressure. If the pressure is greatly different, it can cause the tires to scuff due to having different circumferences, which causes excessive wear and heat buildup.

When traveling in my dually Sprinter, I always give the rear tires a tap with a tire iron as I do my pre-departure checks. One morning in Salt Lake City a few years ago as I prepared to leave the campground, I did the tap routine. Three of the tires gave the usual "bong". The left inner was a "thud". It was a flat I would not have discovered by just looking at the tires. It saved me a roadside tire issue since I was able to get the tire changed at the campsite.

[avanti]

I am not as conscientious as WillieJ. For this reason, I would never drive a dually without a TPMS.

[BillsPaseo]

It wasn't cheap, but I bought this portable compressor, which came with a very high quality 45 degree extended chuck and very accurate built in pressure gauge, along with 60' of hose.

https://www.amazon.com/gp/product/B004B68XGC

I use the hose and chuck in my garage on my 120V pancake compressor, and carry the whole kit (in its very nice carry bag) with me on trips.

This chuck easily reaches the inner valve stems, no extensions needed...

[g1ampng]

We went with the same idea but a more compact version since storage space is a premium. Have needed to use it several times and it's worked great.

https://smile.amazon.com/dp/B005ASY2...t_b_asin_title

[JPMcG]

I am interested in increasing my stopping power with improved front brakes. Pagd, Bimbo and others make slotted, drilled and vented rotors and high friction pads. If I purchase the rotors and pads---will the ORIGINAL MB Calipers FIT?
The Vented Rotors sure look a LOT thicker. 🤓 But none of the manufacturers indicate the need to purchase new calipers as well!! 😳

[booster]

Originally Posted by JPMcG

I am interested in increasing my stopping power with improved front brakes. Pagd, Bimbo and others make slotted, drilled and vented rotors and high friction pads. If I purchase the rotors and pads---will the ORIGINAL MB Calipers FIT?
The Vented Rotors sure look a LOT thicker. 🤓 But none of the manufacturers indicate the need to purchase new calipers as well!! 😳

I don't have any experience on Sprinters, but based on what we have learned with other brands, particularly the Chevies, some brake parameters can be improved a lot and others not so much.


In general, from all the things I have experienced and read about the topic, drilled and slotted rotors do not stop any better than good high quality rotors and the drilled in particular are more prone to cracking.



The best in pads can give you better braking to a degree, and I would expect they would selling semi-metallic or some of the new carbon based pads for that. Some high performance, high friction, pads can wear rotors very quickly so do some research on that.



In the vans, most are set up with fairly light rear braking because in normal use they may be empty and light in the back. In an RV the back is always heavy so more braking can be put on the rear safely in almost all cases. I have no idea if there is a way to increase the rear braking in a Sprinter or not, though, but it may be worth asking.


Generally the best and relatively easy way to increase braking is to increase the amount of boost from the power brakes, so that may be an option if the system can take it.


If you do find a way to increase front braking, you might not like it as the heavy van may dive very hard in quick stops, making it hard to control.



You may want to start be finding out what the OEM pads are made of, as that may give more indication of what might be able to replace them and having a higher friction coefficient.

[JPMcG]

Your response ws most informative. I will re-evaluate my whole bigger brake idea. Yes the weight of a RV stopping with big front brakes --might make for some interesting rear end movements!!!!🥺