Tire size opinions please

[Mark77]

Im gathering up parts to rebuild (upgrade) the suspension on my rig. Going from 6 to 8 bolt wheels, new springs, brakes, obviously bearings... everything except the spring bolts and equalizer that were replaced on my trip last winter after OEM failed.

I ordered and received Sailun's S637 235/85R16 thinking that is what I had. I looked yesterday and what is on the rig now is 235/80's.

Looking up the tire specs, the 85's are about 1" larger in diameter, that means 1/2" radius. Not a big deal to me.

Is there any dis-advantage to putting the 85's on, or is there some good reason I should return them and buy 80's?

 

[Carl n Susan]

The 85's have a higher load capacity.

 

[ChuckS]

I switched from the 80 series to 85 series 13 years ago.. will run nothing but and I DO NOT run at 110 psi cold.. I run at 95 psi cold... Sailun S637 series current tires... four years of use.. even tread wear across the tire... I usually run my tires 6 to 7 years.

 

[Mark77]

I switched from the 80 series to 85 series 13 years ago.. will run nothing but and I DO NOT run at 110 psi cold.. I run at 95 psi cold... Sailun S637 series current tires... four years of use.. even tread wear across the tire... I usually run my tires 6 to 7 years.

Good to know... I mistakenly ordered the wrong size but looks like per Carl and Chuck it will be to my advantage.

I have seen a Sailun chart somewhere regarding running lower PSI to match the load and I will do so. I have a pretty good idea what I weigh loaded so I can figure that out. I don't want the ride to suffer with any increased stiffening of the suspension. Everything stays put in my rear kitchen now and I want it to stay that way!

Thanks for the replies guys.

 

[whitesub93]

I looking for new tire options and I looked and this is what the sticker suggests, LT238/85R16G RV. Does this sound right, a "238" ? Any suggestions are appreciated.

 

[scottz]

No, it does not sound right; never heard of a 238. Either a typo or you misread it. Probably should be 235.

You have not specified which rig you have, but most trailers will spec ST (special trailer) tires instead of LT (light truck) tires. Nothing wrong with running LT tires, but ST are made for trailer service; tandem axles are tough on tires.

 

[Daryles]

Whitesub
LT means light truck.
They have softer sidewalls for a smoother ride.

Trailer tires have VERY stiff sidewalls.
Look for Sailun tires

 

[Carl n Susan]

Actually the original sticker would have read 235/80/R16 but many of us have "upgraded" to the 85 aspect ration for the extra carrying capacity.

 

[PSFORD99]

Actually the original sticker would have read 235/80/R16 but many of us have "upgraded" to the 85 aspect ration for the extra carrying capacity.

This probably should be covered again . Sailun has upped their game a bit on the S637 trailer tires . They are no longer a 14 ply G rated tire ,they are 16 ply H rated

ST 235/80/16 are now rated at 4190 lbs. @ 120 psi.
ST 235/85/16 are now rated at 4540 lbs. @ 120 psi.

I would imagine there are still some G rated S637's at some of the vendors . As time goes on they will get sold ,and the new H rated will be more available . I will be replacing mine this spring, I will be looking for the new H rated .

 

[whitesub93]

This is the tag on the side of my Montana 3582RL

 

[PSFORD99]

I see most vendors are still advertising G rated on their Sailun S637's . A couple vendors I see online have the correct info on them now . Giga Tires ,and Tires Easy are advertising the new H rated . I see Simple Tire ,and Walmart are still advertising the G rated , I am wondering if they are just trying to get rid of their old stock. I bought my last set from Walmart 6 years ago , hopefully this spring they will be selling the new H rated .

I have them delivered to my home ,and I take them off my fifth wheel , and have them mounted ,and balanced at my local tire shop. At the same time they are off , the wheel bearings will be repacked ,and the disc brakes , axles etc checked out .

 

[PSFORD99]

This is the tag on the side of my Montana 3582RL

Same sticker as mine , 235/85/16 , not 235/80/16 . My GVWR is probably less than yours also , mine is 15,500 . I would imagine yours is 16,500 ??

 

[PSFORD99]

No, it does not sound right; never heard of a 238. Either a typo or you misread it. Probably should be 235.

You have not specified which rig you have, but most trailers will spec ST (special trailer) tires instead of LT (light truck) tires. Nothing wrong with running LT tires, but ST are made for trailer service; tandem axles are tough on tires.

I disagree , I’m not sure there are many LT 16” tires out there that will have the weight rating to match our fifth wheels, certainly not the Goodyear G614’s . I think they are still designated a LT tire , but are a trailer application. Those G614's are only rated for 3750 lbs. @ 110 psi , not the tire I'd want on my fifth wheel . Plus the fact they are over $500 a piece .

 

[ChuckS]

I currently run the S637 ST in 235/85x16 and use an air pressure of 95 psi... I will run these hopefully another 4 years... They now have 3 years service on them....

I like the increased load rating of the 16 ply H rated S637T series,, BUT.. the max load rating of the tire at 4550 is based on max cold psi of 120 ... this exceeds the rating of most 16x6.5 on 8 RV wheels which are rated at 110..

However... its. reasonable to assume that the additional two plys will make the tire more sturdy... Its already a very good tire...

Price of the new 637T series tires.... https://www.amazon.com/Sailun-S637T...ca63cd0b6e6d6e21ae7a879&qid=1767718997&sr=8-1

Walmart is also showing the S637T available at a lower price then Amazon...https://www.walmart.com/ip/Tire-Sailun-S637-All-Steel-ST-235-85R16-Load-H-16-Ply-Trailer/16733210735?wmlspartner=wlpa&selectedSellerId=17465&selectedOfferId=4B140341C44C3CCEA48C3A0B632E9CEC&conditionGroupCode=1

 

[PSFORD99]

I currently run the S637 ST in 235/85x16 and use an air pressure of 95 psi... I will run these hopefully another 4 years... They now have 3 years service on them....

I like the increased load rating of the 16 ply H rated S637T series,, BUT.. the max load rating of the tire at 4550 is based on max cold psi of 120 ... this exceeds the rating of most 16x6.5 on 8 RV wheels which are rated at 110..

However... its. reasonable to assume that the additional two plys will make the tire more sturdy... Its already a very good tire...

Price of the new 637T series tires.... https://www.amazon.com/Sailun-S637T-ST235-80R16-16PLY/dp/B0FNY6QJ22/ref=sr_1_1?dib=eyJ2IjoiMSJ9.uvUkMhC6RuGAXt5Ndk9QLN9gCB5ZMyqHtdnNtdQdy9357VxOWQy7ydyG2Rm0ORC5stA2pFsyL8GBLBA-Zr3zSeK4cO_a7uB-o_sG0sirvxZPRNB_-z_T-w3QiAinkGeiUb23WXqbKeupS2jF9uYmu2B6hIPKOVjR90BfHNszwFqZ0nbvpEyTHMyBYTkBr4GihfVPQbScsEGLZNd5JABfhYLYrvy080BjZWTdzDHGBWc.OgiGLsFU44u8ulnF2KalmJGlas4FfBDxQCtPDjmRxmY&dib_tag=se&hvadid=776691233488&hvdev=c&hvexpln=0&hvlocphy=9029579&hvnetw=g&hvocijid=13727635654143308064--&hvqmt=b&hvrand=13727635654143308064&hvtargid=kwd-1849696066305&hydadcr=28717_14955156&keywords=sailun+s637t+st235/80r16+g/14ply&mcid=8228ecc18ca63cd0b6e6d6e21ae7a879&qid=1767718997&sr=8-1

Walmart is also showing the S637T available at a lower price then Amazon...https://www.walmart.com/ip/Tire-Sailun-S637-All-Steel-ST-235-85R16-Load-H-16-Ply-Trailer/16733210735?wmlspartner=wlpa&selectedSellerId=17465&selectedOfferId=4B140341C44C3CCEA48C3A0B632E9CEC&conditionGroupCode=1

I did find the H rated Sailun's at Walmart . Their prices were all over the place , but their H rated 235/85/16's were 189.86 ea. Giga Tires price for the same tire is 157.02 . Looks like Giga would be a good source .

 

[PSFORD99]

Giga , not so good of a deal , there is shipping , my cost would have been $205.67 ea. Walmart is probably the best bet . Free Shipping .

 

[Carl n Susan]

This is the tag on the side of my Montana 3582RL

I can only think you have a Unicorn sticker. Montana may have increased the size of the Aspect Ratio to 85 from 80 (good move) since earlier years. But AFAIK, there is no 238 width, only 235 (in this size tire)

 

[scottz]

This is the tag on the side of my Montana 3582RL

Agree with Carl; I still think it is a typo. Both the LT and 238 seem incorrect. Maybe call Keystone with your VIN and they can shed some light on it. In any case, the ST235/85R16H would be a good tire.

 

[scottz]

I disagree , I’m not sure there are many LT 16” tires out there that will have the weight rating to match our fifth wheels, certainly not the Goodyear G614’s . I think they are still designated a LT tire , but are a trailer application. Those G614's are only rated for 3750 lbs. @ 110 psi , not the tire I'd want on my fifth wheel . Plus the fact they are over $500 a piece .

When I said LT tires might be ok, I also said I did not know what rig he had; still don't know. He might have a 7000# 24' bumper pull; I ran LT tires on those for a lot of years. Looking at his profile I see a picture of a Big Sky; so maybe he does have a heavy 5th wheel; maybe he will tell us....

 

[Mark77]

Re: G vs H... I bought the G's I have on Amazon and the date code shows they were 6 months old when I got them. Just missed the H rated tire update, but considering the update I made from the E rated tires that were OEM, I think I will be fine. Just happy to have a little buffer now on what I consider was a cost saving cut by Keystone given the size and weight of my rig from the factory.