Tire Size - Question

[bw2]

I need to replace the second set of Chinese, tread separating, tires. I want to replace them with Goodyear 'G' 614's.

The present tires are ST235/80R16, the Goodyear's are ST235/85R16. The tire guy said I should check to make sure the width and height of the 85R/16 will not create a problem with clearance.

So, tire guys, can you assist me in this answer?



Thanks

[TLightning]

Lots of us have replaced the STs with LTs in the size noted above...no problems.

[Art-n-Marge]

Very true what Tom says, but to be sure, contact LonnieB for how to determine tire size and how much larger they will be. (Our other MOC tire expert, Glenn of "Glenn and Lorraine" has been offline the past several months undergoing medical treatment).

Also make sure the existing wheels will support the G rated tire at maximum pressure (110psi?). You might not need to inflate them that high, but I don't believe it's recommended to put a higher capacity PSI tire on a less rated wheel.

The Goodyear G614 is an ST tire but it is a much stronger ST tire than what most of us have as E-rated tires. The size you specified is 9.5" wide and 30.7" tall. I hope this helps determine what you need when measured against what you currently have.

There will be other members along very soon to rave about the G614s. They have been a very successful upgrade for many MOCers.

[firetrucker]

The Goodyear G614 is an LT (light truck) tire, not an ST (special trailer service). Goodyear says it is specifically designed for trailer applications, though.

These days, I'd go with a quality LT tire before I'd buy an ST. The LT radial has a more flexible side wall than the bias ply ST, but it's tested to a higher speed rating than the trailer tire. And it's typically cheaper and easier to find than an ST tire. Usually you'll have to go to a slightly larger size to get the same load rating as an ST, but I think you'll and up with a better tire.

Bob

[ols1932]

Amen to that Bob.

Orv

[Jay Bird]

Bob,
After my blow out Sep 08 I changed to 85R/16s with no problems.

[Art-n-Marge]

Well, lookie dat. The website calls it a G614 RST "Designed specifically to handle the demands of trailer application", and the only type/size listed is LT235/85R16 Load Range G. I got confused by the name and it's the type & size that counts, not the name. Thanks for the correction.

I have Goodyear Marathon ST235/80R16 (built somewhere in China) and the dimension of those tires are 9.2" x 30.7" or just a hair thinner (.3 inches) than G614s. I bought these before joining the MOC and hearing about the inherent ST problems.

BW2 - there is a very good chance your existing tires are the same size and if so, being only 1/3 inch wider for the G614s, I would guess they would fit just fine.

Another question related to this topic. I have read that bigger and better tires may not be necessarily recommended for an axle's capacity. I know many members have 7,000lb axles and the G614s work fine but can G614s be used on the 6,000 lb axles and only assuming the wheels can take it? Is there anyone with this combination?

[DnDatGrdJct]

We just replaced the Missions with Firestone Transforce HT tires. I asked the tire person if there was a size difference. If not I was going to keep the spare as a Mission and hope I would never need it. He suggested that we replace all 5 since the Firestones are about one inch larger in diameter. When they are put on you can see a difference in the spacing but there is still a good deal of room. However my tire chocks will just fit now. They did give me $27 each for my Missions in trade. Also had metal valve stems put on.

Dean

[DarMar]

Recently replaced ours with BFG Commercial T/A LT235/85R16E and found in the end we had 1" less spacing between the tires. Our BAL wheel chocks still fit fine with lots of space remaining.

[LonnieB]

bw2,

Numerically, the ST235/80R16 and the LT235/85R16 are the same width at 235 mm, and both fit on a 16 inch wheel. The height is where the difference is, with the LT235/85R16 being about an inch, .92 to be exact, taller. An actual measurement may vary a little from the mathematical calculations, but not enough to be of concern. The answer to your question is yes, the LT235/85R16 will fit your trailer and your wheels and there will be more than enough clearance.

quote:Originally posted by Art-n-Marge.
Also make sure the existing wheels will support the G rated tire at maximum pressure (110psi?). You might not need to inflate them that high, but I don't believe it's recommended to put a higher capacity PSI tire on a less rated wheel.

Art, you are right when you say it's not recommended, but it is acceptable with a few precautions set in place.
1. If a tire ever needs a repair, the repair facility must be made aware of the wheel rating before the repair is made.
2. If the trailer is sold, the buyer must be made aware of the wheel rating before the sale.
3. The maximum weight and psi rating of the wheel must never be exceeded.
You do need to know what the trailer weighs at the axles when fully loaded, and the psi required for the tires to carry that amount of weight. As long as the wheels are rated for the proper load and the psi the tires require you should be ok.

[bw2]

Thanks to all. Thanks Lonnie. At the 2009 fall rally, Tredit checked my wheels and verified they will support 110 psi. I have a letter and stickers for the wheels from Tredit, so I feel ok with the wheels. I do not believe I will need the 110 psi, but the stronger sidewalls etc.. I hope will serve me well.

[mail2us]

Glad to hear you have the 110 rims. I got rid of the Missions, all five and now have the Bridgestone duravis 500's and they have been excellent with our 3400

[thor]

just put the goodyear G614 235 85 16 on my montana 3400 rl went from indiana to ontario canada .no clerance problems at all.put 100 psi in them trailer rode great.i have the steel rims and called the manufacture to make sure the rims can stand the presure.they said no problem

[sailer]

Bob ;;That is what we talked about in brookside;;;I put on goodrich 85/16 and they are taller and closer together but not to give a problem;;; glad you are finaly getting tires from your buddy down the rd a bit ;;;sailer

[northeastdiesel]

I don't have the weight of alot of you, but I took no chances when I got my trailer and bought Michelin XPS ribed tires which are a LT tire. I have read alot of people are using them and they are more than enough to support my camper. When I put some more miles on the camper in the comming months I will send you guys a update report. So far I am very happy with them!

[1Happycamper]

Hi Bob..I also changed my tires last year and went with LT235/85R16. There is no clearance problem at all.
Bill