Tire Advice

[fmoore]

We just had our 2nd blow out with ST tires yesterday. First with a TT and yesterday (only 30 mins into our drive) with our 2013 5th wheel with less than 1500 miles on the RV. I've confirmed the RV is not overloaded; PSI confirmed at 80 prior to leaving and visual inspection looked fine. (I do this every trip and I keep the tires covered). When it blew it sounded like a bomb went off. I would like to get some advice on a recommended tire for our 5th wheel that is 36', weighing at 11,300 lbs (10,200 dry and GVWR is 12,265), wheels are stamped at 3580 so I can't exceed 80 PSI. From posts on here, LTs seem to be the way to go. Went to the shop down the street and they recommended the Michelin LTX M/S 2 10 ply LR E. But, it's rated at 3042 which is a bit lower than the STs on the RV now which is 3520. If I do the math and times 11,200 by 18% (taken off 11,200 for hitch weight) I get 9430 and divide that by 4 I get 2357.50. So on paper these tires even at 3042 would seem to do the job. Any thoughts or suggestions are much appreciated!

[CARLnJANIS]

Our EXCEL L36GKE came with Michelin XTA 17.5" J mounted. They are designed for trailer applications. Have heard nothing but praise for Michelin. However, you may find someone who has a negative opinion of Michelin.


When sizing tires, use the axle weight to determine tire load and air pressure. My 36' GVWR is 18750 lbs. and has two 7500 lbs. axles.

[Randyman1]

I ran into this problem on our 39' 2011 Cardinal that we used to have. Immediately I switched to 17.5 rims and much heavier duty tires. I weighed about 15k and these 17.5 wheels and tires I ordered were rated for 20k. Much more stable pulling and no worries about blowing tires. This was a big topic 2 years ago when I did all this on the Cardinal and other 5th wheel forums. I purchase mine from Trailer Tires & Wheels, google them, they are very knowledgeable about trailer tires. I know switching wheels and tires gets expensive, but your deductible and tearing up the side of your camper isn't cheap either. Randy

[jimcumminsw]

Originally Posted by fmoore

We just had our 2nd blow out with ST tires yesterday. First with a TT and yesterday (only 30 mins into our drive) with our 2013 5th wheel with less than 1500 miles on the RV. I've confirmed the RV is not overloaded; PSI confirmed at 80 prior to leaving and visual inspection looked fine. (I do this every trip and I keep the tires covered). When it blew it sounded like a bomb went off. I would like to get some advice on a recommended tire for our 5th wheel that is 36', weighing at 11,300 lbs (10,200 dry and GVWR is 12,265), wheels are stamped at 3580 so I can't exceed 80 PSI. From posts on here, LTs seem to be the way to go. Went to the shop down the street and they recommended the Michelin LTX M/S 2 10 ply LR E. But, it's rated at 3042 which is a bit lower than the STs on the RV now which is 3520. If I do the math and times 11,200 by 18% (taken off 11,200 for hitch weight) I get 9430 and divide that by 4 I get 2357.50. So on paper these tires even at 3042 would seem to do the job. Any thoughts or suggestions are much appreciated!

When I had my 318SAB Cougar I switched out the tires to Michlien XPS Ribs, these are an all position tires meant for towing. They are an 16" LT tire that will fit your trailer. Mine were LT245/75R/16E. I had 6,0000 LBS Axles on my trailer so I was not concerned about tire loads.

What weight axles are under your trailer? Remember that at least 20 to 25 % of the trailer weight is supported by the truck rear axle.

Jim

[fmoore]

Jim - thanks, the axles are 6000's. I was cautious in my % of weight on the rear axle for my truck using 18%. So if 20-25% is more the norm then that 9430 for weight on the trailer axles would be lower.

[FastEagle]

Originally Posted by CARLnJANIS

Our EXCEL L36GKE came with Michelin XTA 17.5" J mounted. They are designed for trailer applications. Have heard nothing but praise for Michelin. However, you may find someone who has a negative opinion of Michelin.


When sizing tires, use the axle weight to determine tire load and air pressure. My 36' GVWR is 18750 lbs. and has two 7500 lbs. axles.

Great tire except it's a European designed tire and has a maximum speed rating of 62 MPH.

Tire and Retread Selector | Michelin Truck

[FastEagle]

Originally Posted by fmoore

We just had our 2nd blow out with ST tires yesterday. First with a TT and yesterday (only 30 mins into our drive) with our 2013 5th wheel with less than 1500 miles on the RV. I've confirmed the RV is not overloaded; PSI confirmed at 80 prior to leaving and visual inspection looked fine. (I do this every trip and I keep the tires covered). When it blew it sounded like a bomb went off. I would like to get some advice on a recommended tire for our 5th wheel that is 36', weighing at 11,300 lbs (10,200 dry and GVWR is 12,265), wheels are stamped at 3580 so I can't exceed 80 PSI. From posts on here, LTs seem to be the way to go. Went to the shop down the street and they recommended the Michelin LTX M/S 2 10 ply LR E. But, it's rated at 3042 which is a bit lower than the STs on the RV now which is 3520. If I do the math and times 11,200 by 18% (taken off 11,200 for hitch weight) I get 9430 and divide that by 4 I get 2357.50. So on paper these tires even at 3042 would seem to do the job. Any thoughts or suggestions are much appreciated!

Even though your OE tires are rated at 3520# they default to 3420# unless they are documented somewhere other than on the tire’s sidewall.

With 6000# axles on your trailer you have to be logical about replacements. If the trailer’s manufacturer will not recommend - and I doubt they will - LT tires with a lower load capacity you’ll be on your own with any replacements below 3420# of load capacity.

RV trailers are notoriously unbalanced. Seldom will anyone having their trailer scaled for the first time find actual tire weights from side to side or axle to axle very close to what the others are carrying. So, in a perfect world with all tires capable of 3042# of load capacity at 80 psi you’re probably going to find one or two carrying more than they are capable of. Most of the tire experts posting on tire forums will recommend at least 12-18% extra (reserve) load carrying capacity above the trailers certified total GAWR.

[Triker56]

If I do the math and times 11,200 by 18% (taken off 11,200 for hitch weight) I get 9430 and divide that by 4 I get 2357.50. So on paper these tires even at 3042 would seem to do the job.

Only way to do the math right is to weigh truck and then both sides of the 5th axles separate. Then do the math. Otherwise you will never know if one side is overloading the tires.

[grassy]

Moved to LT tires. Worked out max weight of trailer..went a bit higher..stayed with the 90 psi rims..

I am in no rush and not a speed demon..but have had 2 blow outs with ST tire on my last rig and no longer believe the drivel of the "stay with ST tires l" you get at the RV store...

The info that really swung me was the testing procedures and the tolerances that the LT vs ST tire has to go through..

That is my 2 cents ..your mileage may vary...

[justafordguy]

I agree 100%, I went with a commercial LT235/85R16 LR G tire on my Gateway. The commercial LT tire is a much more heavy duty tire.

[timetogo]

FYI: Rims stamped 3580 doesn't mean they are limited to 80PSI. It means 3,580 lb load rating.

That said, I'm sure you can find tires that will do the job with 80psi.

[CARLnJANIS]

Originally Posted by FastEagle

Great tire except it's a European designed tire and has a maximum speed rating of 62 MPH.

Tire and Retread Selector | Michelin Truck

I don't drive much faster than 65 mph. I may push it up to 70 or 75 mph if the DW is sleeping. Normally, I'm not in that big of a hurry. About 400 to 500 miles distance is our usual limit. Going 75 mph the whole way would save only about an hour.

[cb1000rider]

Sailun ST235/85R16 tires. They weigh about 60 lbs each. The remind me of a mini-version of the Michellins that you see on DPs.

3750 each at 110 psi. I run 90 psi in mine on wheels rated for 3750 and 110 psi.

Simpletire.com

[justafordguy]

Originally Posted by cb1000rider

Sailun ST235/85R16 tires. They weigh about 60 lbs each. The remind me of a mini-version of the Michellins that you see on DPs.

3750 each at 110 psi. I run 90 psi in mine on wheels rated for 3750 and 110 psi.

Simpletire.com

Same thing I run, Awesome tires so far.