Any recommendations for a valve stem extension for my inner dual tires? It’s a pain in the Butt to try and adjust the pressure. Thanks!

 

Bump +1, I'd be in for a set of good ones.

How about this one, I just took my truck to the dealer for its first oil change and I specifically asked the Service Writer to have the tech check all the pressures as part of it the service.
Comes back with the tech couldnt check the inner rears,,, at a FORD Dealer that sells Ford duallys. You would think they would have the right tool for it since this is exactly how they sell the truck.
So lame.

 

that is absolutely incompetent. Lol mine would probably lie and say it’s fine.

 

@Flitastic @Jimmy Pet

I found a set of good ones, from Germany. Unique, ultra lightweight materials. Non pressurized. Quite stiff, for less susceptibility to centrifugal whipping. Yet flexible enough to resolve any angular difference between the projection angle of the factory valve stem on the inside dual rim, and the inner axial perimeter of the hand hole opening on the outside dually rim. In fact, the modulus of elasticity of the unique material can tolerate severe manual bending, but left alone, the material is stiff enough (and light enough, reducing the influence of its own mass) to be used without any stabilizer brackets or wires.

Anyone who knows me knows that I just don't put any 'ol thing on my truck that I read about, see advertised, or find on sale. Especially when it comes to safety, and especially where the rubber meets the road. These are not areas where I relax. I've owned a dually of some sort for the last quarter century, and have not run inside dually valve extenders because of all the problems in actual usage that many are already well aware of, and proof of that awareness is confirmed by the search for "a set of good ones."

The bad ones include those that are pressurized, such that when they get severed from a road hazard, the inside dual looses all air.

The bad ones also include those that are heavy, such as the thick braided stainless steel type, which can not only contribute to rotational balance concerns, but can also whip around more from their own mass.

The earliest bad ones, without any stainless steel braid protection, saw failures from impacts, as well as the same limited lifespan that the rubber tires themselves have. Exposure to ozone, UV, chemistry in the exhaust, heat from the brakes. all contribute to rubber degradation, and even when not exposed to elements or use, rubber degrades over time anyway.

When the "live stem" non pressurized extenders were introduced (by the likes of Wheel Master, Dicor, Phoenix, and other vendors in the late 90's), they were notably thinner in cross section than the fully pressurized versions that continued to be sold at a lower price point. I almost bit on these new live stem versions back in 1998, but held back, to see how they would fare. It didn't help that Ford began using TR600HP brass sleeved rubber based snap in valve stems on dual rear wheels at the time (Ford later returned to all metal clamp in on DRW applications, up until relatively recently, with the expansion of TPMS). So what actually might have failed in many of the subsequent user reports was the rubber stem base (from the whipping) rather than the extender, but typically the evidence was lost on the highway, too far back to retrieve by the time the victim was able to safely pull over.

So that brings up Step #1 for ANY extender. Make sure to have all metal clamp in valve stems. Whether TPMS or not, the clamp in base is needed to withstand the leverage of an extender. Snap in valve stem bases only have enough holding power to retain themselves, not the addition of an extender.

Some folks have taken this idea a step further, and have put in tractor clamp in valve stems on the inside dual wheels. That gives them 5 or 6 inches of solid brass, pre bent at a satisfactory angle to aim through the hand hole of the outside dual rim. No whipping. HOWEVER, now two wheels are committed to only be used on the inside dual position. This negates tire rotation, which is no big deal, because it often isn't a good idea to rotate matched dual pairs anyway. Better off leaving the drive axle alone and just rotating the steer axle tires side to side, and work in the spare if running all steel wheels.

But the real deal breaker on the dedicated "dually valve stem" on the inside duals is not being able to swap tires around in an emergency. Chassis cabs that don't have a dedicated provision under the truck to carry a spare are often caught on the road without a seventh tire onhand. An advantage of DRW is that a flat tire on the steer axle can be fixed by using one of the rear tires in a dually pair on the front. Sure, that rear tire can, and should be, the outside dual, rather than the inside dual, but then when it comes to rematching tires and wheels again, especially in a fleet of similar trucks, having overly long and awkward non removable valve stems on a few wheels really limits options, when trying to balance tire wear, and meter out new tire purchases with a minimum of fuss breaking down tires from wheels that otherwise wouldn't need separating.

Still the dedicated long ridged tire valve is a workable option for individuals, and there is a website having a similar name that sells kits to accomplish this, but a knowledgeable tire person can identify the trade number for the length and angle of solid brass valve stem (or even better... nickel plated brass for more corrosion resistance), and commit two wheels to inside dual duty only with a change in valve stem.

But I didn't like that option either. So I did without, until I was introduced to the extenders from Germany that I am using now. A Goodyear Truck Tire manager actually gave me a pair for evaluation back in 2014 (I have no interest or affiliation with Goodyear nor the valve extender manufacturer), and I set them aside and promptly forgot about them for about 4 or 5 years. Then a couple of years ago, when spec'ing out a 2019, I had reason to revisit the inside dual tire valve extension question again, and through research encountered very favorable reports of the extenders that I vaguely sort of recognized as having seen before someplace. Aha, there they were, in one of my own parts drawers. I mounted them, and added spring wire stabilizers from a Dicor kit that I also had on hand, and included a grommet for good measure. It's been two years now, which isn't really a long term personal evaluation, but combined with the self-evident differences in the materials used for these extenders... color me favorably impressed.

I'll revisit this thread with photos, and the brand name (it escapes me at the moment), when it is daylight, so the camera and I can actually see the parts.

 

@Y2KW57 -
Wow thanks for the great detailed reply. LOL I think I have tried all or most of the "bad" ones you described over the years on my other duallys. Thats why I had pretty much given up on ever finding a "good one" (until I saw this thread).
I look forward to the additional info.
Thanks again
jimmy p

 

Following! We have a big and heavy truck camper on our 2017 F450 dually. Been looking for a good solution for valve extenders for the inner duallies since I bought the truck.

 

@Flitastic @Jimmy Pet @johnpitts01

Let's begin with the added weight whipping around with a tire valve extender. This isn't weight on the wheel, it is weight hanging off and centrifugally leveraged away from the wheel.

The first photo below is a typical (and comparatively short) inside dual valve stem extension of rubber with a stainless steel braided jacket.



Now we can compare the typical dual tire valve extender shown above with the German designed and manufactured dual tire valve stem extender shown below, sitting on the exact same scale:



Because the scale is cylindrical, it is hard to get an accurate reading without looking at the needle head on, which is hard to do when trying to also photograph the extenders sitting on the scale, so let's take a closer look at just the numbers.

Again, we will start with the typical stainless braided wrap over rubber tire valve extender, weighing in at 47 grams:



And we will compare the weight reading above to the weight reading of the ultra light weight German tire valve extender below, weighing in at only 17 grams, which is a 64% reduction in rotationally whipped mass:



One might ask, "Are the two different types of valve extenders the same length though?" Yes.



So what is "air-flexx"?



Ok, how about we run that by again in plain English?
































And finally, a dimly lit shot of how I installed these air-flexx extenders in my 5 hand hole 19.5" wheel diameter dually:




For more information comparing the strengths and weaknesses of different types of dual rear wheel tire valve extensions, check out this pdf chart with more photos:

Fuhrpark-Check-De.pdf

For more information about the DEKRA agency certification for these tire valve stem extenders, you may read it here (if you read German) or use an online translator:

Gutachten-Nummer 309/1597/05-1109323770

Additional photos, applications and information can be found in the product brochure pdf below:

UNBREAKABLE PRESSURELESS High Quality Ventilverlängerungen

To see the biggest, largest dual rear wheel tire valve extender that I've ever seen in my life...

„Ich hab’s verstanden! Und Du?“ = "I understood! And you?"

And one more informational flyer...

Absolut drucklos & bruchsicher - Die hält immer! (Absolutely pressureless & unbreakable - It always lasts)


Air-Flexx Website:

www.air-flexx.com (redirects to) www.air-flexx.biz

Distributed in the United States by

Meyers Tire Supply

 

That website aint no good unless you can read German or whatever the hell that is.

 

It's German, I haven't spoken or read that language in 20 years & even when I did I was bad at it

In a nut shell Air-Flexx is superior in all ways and all other products are inferior. Air-Flexx has no failure risk all other valves pose some sort of failure risk.

I do need to air up my tires this weekend, so I'll see how hard of a job it is. I might find myself buying a set of these.

 

I think I'm going to pick up a set of these for my F-450.

Using Google translate made it easier to understand - https://translate.google.com/transla....air-flexx.biz

This US distributor has an online shopping portal for these - https://shop.myerstiresupply.com/ERP...222:3100023201

 

A properly angled air chuck/tube will reach the inners. Then theres no need for extenders, balance issues, and safety issues.
If the chuck angle is not right, bend the chuck tube a little.

My new 19.5” inners on my 350 are a real pain to get onto. But im not going to chance some debris or rocks hitting my extenders and cause a deflation.

Like most things, extenders will cause some compromise to be made.

Again. a proper angled chuck & slightly bent tube will get the job done easily. Adapt the tool not the equipment.

 

What size are you ordering?

 

I'm debating on either the 5-11/16" or the 7-1/4". The 5-11/16" would bring it out even to the base of the outer valve (when I measured it, it's close to 6" from the tip of the valve on the inner dual to the base of the valve on the outer dual) the 7-1/4" might be a bit too long. Might get both to see which works better. The inner valve has bit of an angle, so maybe the longer extender will be easier to work with. Without one, it looks like it would be a pain to try and get an air chuck on the inner valve.

 

As you can see from my measurement photo, the actual length of the ones I have is approximately 155 mm net length overall (6" = 152.4 mm, plus there is a tiny bit of overhang)



As the published size option listed on the package that is closest to the actual length physically measured appears to be 145 mm, I'm assuming that is the size that I have.

I would not get less than 145 mm. I would also not get greater than 185 mm, which may end up being actually more like 195 mm if the same means of measurement applies.

I have all steel wheels, which are thinner than aluminum, but I also run stainless steel skins (not shown in my installation photo above), which float outboard a bit a way from the outer dually dish by an amount greater than or equal to the thickness of an aluminum wheel.

The installed length, and how far the end emerges toward, through, or beyond the outer wheel hand hole, will depend on the type of valve stem the extender is being attached to.

This is important to consider, because some 2017-2020 F-350 and F-450 owners with aluminum wheels have had wheel corrosion issues at the valve stem hole interface, that they have attempted to resolve with changes in valve stem types and materials.

I highly recommend clamp in valve stems, not rubber based snap in valve stems, if extenders are intended to be used, even light weight high tech material combination extenders such as these German air-flexx models.

The installed length can be extended by a little over 3/4" (20mm) by attaching a double sealing inflate thru self closing valve cap, such as a brass V2B by Dill (former Ford OEM, before Ford went China), or a DS-1 by Haltec (preferred, due to the nickel plating over the brass).

By the way, speaking of Haltec, Haltec supplies tire valves for the heavy construction industry (mines, quarries, earth moving, grading, where tires on digging equipment and dump trucks are abraded by freshly cut sharp edged tire flung rocks).








Haltec distributes and recommends these Air-Flexx tire valve extenders.

Since this is post is in answer to what length of air flexx to buy, here is Haltec's arrangement of sizes and part numbers in inches.



I recommend going as short as possible, but not so short as to not reach through the outboard wheel hand hole, especially with aluminum wheels, that have hand holes that no hand can reach through.

Those with aftermarket wheels that are wider to fit bigger tires, and that may have different hub plane offset and wider dually spacing, might want to measure the actual distance between inside valve stem (at end of cap threads) and outside dual rim on their own unique tire wheel combinations.

 

Thanks Y2KW57 for the detailed info, it certainly helps in the decision process. Given that information I'm going to go with the 145mm/5-11/16" length which should allow easy enough access to air up the tires. Surprisingly they were available on Amazon for less than $40 which ended up costing me nothing as I had some gift cards from the holidays .