New user, TC Tire questions

I am still seeking an answer to the question of whether or not an F load rated tire with a 128 load index (305/65/18) or an E load rated tire with a 129 load index (295/70/18) would be preferable for a TC hauling application.
What makes it an F rating if not increased load?
Will the F rated tire have significant stiffness/robustness?

Thanks!

Great information rider997, thanks!
Our intended use will be similar to what you describe, dropping the camper at camp and using the unloaded truck to drive to trailheads for biking/hiking/skiing/etc.

My engineering background had me questioning the damping of the timbrens, I'll have to do some additional research on the super springs. One of the reasons I liked the stableload concept was that it leveraged the existing progressive spring pack which has excellent sway control/damping by design. I am unsure how much negative rake I will have once the camper is installed and if the stableloads will correct it. I was under the impression that removing the pin to dis-engage the stableload was trivial but maybe I am wrong. Obviously, the camper would need to be removed. My truck will not drive a lot of miles without the camper, really only up to the ski resort when conditions dictate or out on forest/logging roads. It is not a daily driver. I liked the idea of being able to remove the suspension modification for these uses.

skimopow wrote:
threeaces:
I went to Les Schwab to get a quote for a 19.5 tire/wheel setup and they recommended the Michelin XDS2 in a 245/70. My calculation showed a 126# vs 87# OEM vs 100# upgraded 18" per wheel weight. Good to hear that you don't notice a massive decrease in unloaded ride quality as that is a concern. My F350 does feel very stiff in the rear already. I have heard that the bump up to 19.5's can necessitate upgrading shocks to manage the un-sprung weight. I am leaning toward the 19.5 setup, but I have read that you can get the same tires in different load ratings (G or H) but it appears that Michelin only makes 245/70 in an H rating.

You and I have the same family setup, no surprise you settled on the AF 811 !

rider997:
Re: the upper stable loads, the dealer recommended the upper stableloads, but torklift recommended the lower stable loads so who knows. I have no rear sway bar so a Hellwig rear sway bar is on the list. Do you think supersprings are preferrable to timbrens?

Have you run 19.5" tires in the snow or did you decide to stick with 18" because of snow performance concerns ?

There are 19.5" tires that people insist perform great in the snow. That hasn't been my personal experience. They are also less versatile in that they can't be aired down (with the camper off) for good off-road traction. We oftentimes dump the camper and drive fire roads with the bare truck (and the LT tires aired down).

I have used Timbrens and think they're fine for simple payload applications (carrying bricks). They don't have any meaningful internal damping and they exacerbate bouncing and sway for a truck camper. Getting enough support for heavy payload applications (2 tons for a TC) also results in a terribly harsh and annoying unloaded ride. The Supersprings pleasantly surprised me with their loaded and unloaded performance.

Lower Stableloads are the least expensive way to prototype the feel of a heavier spring pack (compared to any air spring/rubber type of suspension like airbags or Timbrens). I don't have any intention of jacking up the truck to remove tension on the lower Stableloads to disengage them, so the bolt-on capability and significant suspension lift of the Supersprings was my preference. My truck carried my camper fine with only stock suspension, but went from a positive rake to being an inch or two below level in the rear- this means that headlight aiming was off, and I was removing weight and traction from my front axle.

threeaces:
I went to Les Schwab to get a quote for a 19.5 tire/wheel setup and they recommended the Michelin XDS2 in a 245/70. My calculation showed a 126# vs 87# OEM vs 100# upgraded 18" per wheel weight. Good to hear that you don't notice a massive decrease in unloaded ride quality as that is a concern. My F350 does feel very stiff in the rear already. I have heard that the bump up to 19.5's can necessitate upgrading shocks to manage the un-sprung weight. I am leaning toward the 19.5 setup, but I have read that you can get the same tires in different load ratings (G or H) but it appears that Michelin only makes 245/70 in an H rating.

You and I have the same family setup, no surprise you settled on the AF 811 !

rider997:
Re: the upper stable loads, the dealer recommended the upper stableloads, but torklift recommended the lower stable loads so who knows. I have no rear sway bar so a Hellwig rear sway bar is on the list. Do you think supersprings are preferrable to timbrens?

Have you run 19.5" tires in the snow or did you decide to stick with 18" because of snow performance concerns ?

skimopow, any of the options you are considering will have more than enough capacity for hauling that camper.
I'll suggest that even OE wheels with OE or upgraded tires will run safely, as evidenced by the thousands of trucks doing it daily, year in and year out.

I'm in a similar situation as you too. I just ordered an AF 811 that will be ready for me the first part of January.

I had a Lance 650 (the lightest hard side with all the amenities, about 2,500 lbs loaded) on a Ram 3500 short bed with no suspension upgrades. Now that I know I'll be somewhere around the 4,000 mark I realized I'd need to beef the truck up.

Seems everyone is in agreement that tires are the weakest link. I, like you, had E rated tires rated to 3,640 each. I could have opted to go to the 4,000 rated tires but instead jumped to the Vision 19.5 wheels with Toyo 920A's. Now I'm rated to 4,500 pounds with a 14 ply tire. Obviously its great to increase each tire almost 1,000 pounds, but for me peace of mind was important. It was costly, but consider the total investment......truck + camper + gear. New wheels/tires is a somewhat small percentage.

I also opted to do Firestone Airbags and lower Stableloads. My hope is to have both adjusted so they work together. I'm a firm believer that you need to use your suspension and not just have the weight sitting on two over inflated balls (airbags).
Lastly, I added the Hellwig sway bar. It's beefy!

So in the end I'm sure my stock wheels/tires would have gotten the job done. However, I plan to put many miles on the truck/camper combination and as mentioned earlier, peace of mind is so important to me. My travel will include fishing and hunting, which brings in boat ramps, gravel roads, dirt roads, etc. A good tire is key. Oh, and another thing.....the Toyo 920A's have the "mountain snowflake" symbol. I wanted a good winter traction tire. We both basically will encounter the same roads and weather so I'm sure you can relate.

PM me if you want photos or pricing details on my wheels/tires. I opted to go with Les Schwab. Yes, I paid more.....about $400-$500 for the package, but it was worth them dealing with everything. Valve stems (TPMS) can be challenge and now that they did everything I know I can go back and they will take care of any issues. My other option was to order online and then have a local shop install. Don't forget that these are not normal passenger or light truck tires. All shops won't install......most can't.

One more thing. I've only had the tires for a few days, maybe 75 total miles. They are a little "squirmy", but not too bad. I hear they will settle in. The ride is slightly (like I can hardly tell the difference) more firm, but honestly my 3500 rides really rough anyway. The day I drove it off the lot it was stiff. I just feel this is part of the deal. If you want a truck with a lot of payload then by nature it will be stiff unloaded.

Good luck and I know you made a good choice with the 811. After my research, the 811 was the clear winner for what I need.

skimopow wrote:
I'm new to the forums and eagerly awaiting delivery of my Arctic Fox 811 (my first TC). I have extensively read the forums here researching this purchase and have settled on the Arctic Fox mated to a SRW F350. I will install both upper and lower stable loads as my first suspension improvement to the stock truck with a sway bar and potentially Timbrens down the road.

When it comes to tires I feel like I have a few options. I will wait until I take delivery of the TC and get a chance to both drive it and weigh it before making a tire/wheel purchase.

I see 3 legitimate options to increase tire/wheel capacity of my stock truck. OEM wheels appear to be rated at 3615# based on a rear axle rating of 7230#, tires are 3640# per tire. My rear axle weighs 3180# unloaded. Based on others AF811 weights I am guessing 4200#+ wet which puts me above the OEM ratings.

The 3 options I am considering are:

Method HD wheels rated to 4500# each mated to:

A.) Nitto Ridge Grappler 305/65/18 F 128
This tire has an F load rating but a 128 (3960#) load index

B.) Nitto Ridge Grappler 295/70/18 E 129
This tire has an E load rating but a 129 (4080#) load index

C.) Vision 19.5" wheels rated at 4500# mated to:
Michelin XDS2 245/70/19.5 H 136 (4940#)

I have read tons of opinions on 19.5" vs 18" and talked to my local tire supplier regarding this choice. I drive on logging/forest roads frequently and in the snow. Wet roads are normal here 6+ months out of the year. I have never had a need to air down my tires with my previous truck, unlikely that will be an issue with the new truck.

My questions are:
1.) Is there a benefit to the F load rated tire over the E rated tire ? Obviously, the E rated has a higher weight capacity, but is there a stiffness or robustness advantage to the F rating?

2.) The un-sprung weight of 19.5 wheels/tires is unappealing (126# vs 100# per tire/wheel) BUT from my research it appears the increased sidewall stiffness of the 19.5 is a big advantage for hauling a truck camper. Is there a huge difference between these options? Will I regret not going 19.5?

3.) Traction with the wider 18" tires will be far superior to the narrower 19.5" tires. Because I am a skier and in the snow 6 months out of the year will the 19.5" tires be a major downgrade from the OEM 275/70/18 Goodyear Wrangler Adventure tires?

I have considered keeping the OEM tires if I go 19.5 to use in the winter.

4.) Because I am very close to the OEM ratings does it make sense for me to go to 19.5 with all the disadvantages (cost, unloaded ride, etc.) ?

This community seems amazing and I have found answers here no one else could provide, hoping to glean some insight from the experienced users here!

Thanks!

This isn't answering your question, but with my SRW 3500 Chevrolet I found that upper Stableloads were nearly useless. I played around with suspension options and found that a Hellwig Big Wig swaybar, Supersprings SSA-13, and Bilstein 4000 series shocks provided the best ride performance.

Also, I am under specified weight ratings on my rear tires and wheels with an 811. I also drive extensively in the snow and do not think the performance of 19.5" wheels is adequate. They also make the unloaded ride of the truck even worse since they can't be aired down like normal load range E tires.

Welcome! I'm too far out of a TC to comment but you will get lots of responses.