• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!
    CLICK HERE TO REGISTER!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

19.5 dually wheels

Twisted Steel Performance

Anything worth doing is worth overdoing.
Messages
3,982
Reaction score
7,584
Location
Pauline, SC
19.5 downsides
Availability of 19.5 tire is usually worse. I’m sure you will have a spare, but if you run over something and need 2 new ones. Any tire shop is gonna have something to get you by in the smaller size, but 19.5, not as easily.
On the more rigid sidewall 19.5 tires, some of the cheaper/ older tire machines have a hard time.
 
The tires on your truck will carry it to it's load capacity. To be clear you are not going 19.5" to get more load or towing beyond the limit of the door weight sticker. Now you can convert to SRW with the 19.5" and still have tire capacity left over from the door sticker vs. the dual LT's. The 19.5" have that much more load carry capability than the LT's. So advantage #1 is 4 vs. 6 tires on the road.

19.5" tires can go 100K miles were the 16 LT's are good for 20-50K miles. The 19.5" can be a bastard to balance including out of round. You need a truck stop to work on them as common tire shops won't touch em. If you run one low they can "zipper rip" blow out the sidewall injuring anyone near them. They ride stiffer. The traction from the hard rubber is less than LT's. They are heaver. It's 110PSI and you can't air em down much unloaded like LT's that are 40-80PSI. My air compressor doesn't go much higher than the 19.5" tires need(!)

I looked long and hard at converting to 19.5" to haul a slide in camper. IMO the long life would "age out" the tire before I got the miles out of them. The door sticker ultimately shut me down. I would have had to start with a DRW vs. the SRW I had.

And you are paying how much more for the rims and tires to get all these problems...
 
Oh, definitely more work for them. But I wouldn’t rule it out easily. If you know your gonna put the miles on them, it could be worth it.
Road force balance is always a worth while investment. Another option to help with that is centrimatics or balance masters. Hummer owners learn this quickly with stock tire size of 37x12.50x16.5 - with the Factory beadlock/runflat each wheel comes in at 165 lbs.
And yes the sidewalls don’t absorb the small bumps like the big & soft sidewall ones. But imo improved suspension to handle that and not the tires helps ride and control in anything from sports car to semi truck. Adjustable ride shocks help a lot and removing some of the leafs and replacing with air bags do wonders.
 
I did think about all that has been mentioned above, I just wanted to make sure I was thinking straight...

I'll stay with the tire choice and with the 16" wheels I have, and the GN trailer uses the same size wheel & tire combo so that will make spare's easy...

I'm off all next week, so the plan is to swap tranny, all new clutch stuff, I have Firestone air bags to install so I'll drop the overload brackets on the frame, lower the rear 2" for a level ride height, and lastly start the install of the rear disc kit, all I need for it is the right proportioning valve...
 
They are factory on the 3500HD's from the 90's, stock size is 225/70/19.5 but I'm running 245/70/19.5"s (true 33"). Each tire has a load rating about 4,000 lbs and when not towing I'm at 65psi which is about the lowest to go with a safe reputation at lighter weights. Common lighter duty tire places such as Discount Tire do carry and will work on 19.5"s in my experience with their common sizes (225/70 and 245/70). Some of the lightest weight rating tires I've found are a load range F and the tires on my truck are some of the more offroad aggressive tread patterns.

Towing it's a nice upgrade in stability and never having the tires near their max capacity. Long life span, even the cheap tires have a 50k+ lifespan usually, quality ones can be around double that. Harder to puncture the tire (I've run over quite a few cactus plants, one of the 235/75/16"s on the old dually got a flat from those same spines). Very stable on the road. Using balancing beads in mine with good results.

Downsides in my experience, rougher ride, higher up front cost but cheaper in the long run, and initial break in. 19.5 tires are well documented to be slick in light rain conditions for the first few thousand miles. Offroad traction isn't as good because they can't be aired down enough to flex and the sidewalls are not capable of even doing that.

My opinion, if the truck is mostly on pavement and hauling heavy weight often then 19.5"s make sense. If more of a general purpose rig, non commercial sizes like 16"s are a better fit. The more aggressive 19.5"s like mine will handle dirt roads/minor trails fine but only as good as a decent A/T tire at full pressure.

20200623_201450.jpg20200707_143558.jpg
 
Just curious, what rear disc kit are you using. I've wanted to convert my dually to disc but can't find a axel already built.
 
If there is any thought about re-gearing, going with 19.5" wheels can prove easier and less expensive by changing tire size. Not as much flexibility of doing this with 16" wheels as the OE tire size is near the max height already. As an example, on my one vehicle, I am going to go from 16" to 18" as I need tires anyway and the wheel upgrade will cost less than having a shop re-gear both diff's. Net effect should take me from 3.73 to 3.55 in terms of engine rotation. Having lower rotational speed of the wheel is a bonus in my perspective as it is less friction at the bearings.

Watch for use in winter weather as the tread patterns on 19.5's might not have the same advantage as what would come on a 16" wheel. Yeah, sure, it does not snow much in SC, but if you go a wandering . . . ;)
 
If there is any thought about re-gearing, going with 19.5" wheels can prove easier and less expensive by changing tire size. Not as much flexibility of doing this with 16" wheels as the OE tire size is near the max height already. As an example, on my one vehicle, I am going to go from 16" to 18" as I need tires anyway and the wheel upgrade will cost less than having a shop re-gear both diff's. Net effect should take me from 3.73 to 3.55 in terms of engine rotation. Having lower rotational speed of the wheel is a bonus in my perspective as it is less friction at the bearings.

Watch for use in winter weather as the tread patterns on 19.5's might not have the same advantage as what would come on a 16" wheel. Yeah, sure, it does not snow much in SC, but if you go a wandering . . . ;)
I had been wondering about the 18" wheels and tires for My 2000 K3500. I see quite a few take offs for sale over here. Biggest problem, I think its a problem, is the wheels are mostly for the newer pickup trucks and I doubt the lug pattern is the same.
Most of them are from Ford and Dodge units.
The truck is currently 4:10 diffs, and I would love to get to the 3:73 ratios, maybe the 18" wheels can doodat, except then I`d probably need about a 6" lift kit. LOL
 
19.5 is very different than a 18”, 19” or 20” wheel/tire.
They are specifically heavy duty sized. Really stiff sidewalls which improves tire life but makes ride rough. Even 20” wheel with same height sidewall, the 19.5 is stiffer sidewall and much higher load rating.
Specifically engineered for industrial use, not cozy truck ride. The truck suspension can be modified to ride as nice or nicer.
Long term money saving after bigger investment, and harder to get serviced.

So don’t mix concept of 19.5 with other near same size set ups.
Kinda like lo pro hd trailer tires vs kia car tire. Similar size- way different out comes.
 
So will You install the G rated tires on the fronts

Realized after your reply that I had a typo in mine hahaha. 4 of my tires are G, the 2 new one's are H.

The H tires are installed up front and the 4 G rated tires are on the rear. F's would be better for my use but haven't found any with that weight rating in the 245/70/19.5 size. Rear axle in the HD's is rated for 11k pounds.
 
Glad I found this thread. I've been looking for a reference setup for dually wheels. I want additional payload and towing capacity in reserve for the truck camper. I'm afraid I might mess up if I try to add spacers so I have to get a mechanic for feedback and more insights.
 
I've been curious about converting to rear wheel disc brakes too, thanks for the lead Chris!

Do you know if replacement rotors for the kit can be sourced from anyone other than the company that supplies the kit? Access to parts is always something to consider out here in the country...
 
I've been curious about converting to rear wheel disc brakes too, thanks for the lead Chris!

Do you know if replacement rotors for the kit can be sourced from anyone other than the company that supplies the kit? Access to parts is always something to consider out here in the country...

I know the calipers & pads are stock caddy I think, the info is on their TSM's site me thinks and the instructions... the rotors I don't know, I'm guessing they may be TSm only...
 
Back
Top