1/2 Ton PU towing tire - need brand and model assistance

[JohnB]

Hi Fellow Sunline Club Members

Truck tires can make or break a stable towing experience. The combination of the truck suspension, tire makeup, tire pressure and the TT make up can be a hard combination to sort out some times. Tire pressure experiments have proven to help but in some cases you are at the difference of 5 psi being a stable system and a non stable system.

From that end need I am reaching out to fellow Sunline owners and some input on brands/models of P tires that have been known to tow stable ideally on the newer 2007 and forward, GM 1500 PU’s. And ones that are known to have issues with too much side wall flex. We are not exactly hung up on the Chevy’s; Ford, Dodge and other brands are OK to throw in the mix as well as well as other year trucks.

I'm helping a buddy correct the setup on his towing rig. This rig has had towing issues since the day he started camping. I have helped him reset his WD hitch and anti sway control so that is now in line and we did weigh his TT tongue with my Sherline scale. The last thing to sort out is the truck tires. He is on the edge of being stable and not. We are now into the tire pressure experiments. He is going to buy new tires before winter due to wear and I’m trying to see if there is something better in wall stiffness before he buys them to help with the towing.

A little background so you know more about the setup

Truck: 2007 , 1500 Silverado, (new design for 07, not classic) extended cab, short bed. Now running OEM stock tires Goodyear Wrangler ST P265/70R16’s Max psi 44.

TT is 24’ 4” long, 600 # loaded tongue weight and in the 5,050# loaded GVW range. So that is 11.8% loaded tongue. The GVW is estimated as he does not yet have a scale value but seeing his setup it is in that range.

Hitch is a Reese HP trunnion style 800# bars and has the DC.

So he has good wheel base on the TV, a good hitch with anti-sway, tongue weight is OK although I would like it a little heavier but being 13% verses 12% tongue is not going to globally shift this setup. The TT is within the ratings of the truck and running stock OEM tires.

When he left me last we had the rear tires at max cold. 44 psi. The front was at 40 psi. TT was at max cold, 50psi. He found the front end, sensitive, and it bounced left and right some when he went over the 1st railroad tracks. That made him nervous and he aired the rear tires down 5 psi and the rig went really bad. Not knowing what else to do he aired the front down into the 35 area and they made it home.

This week he headed out camping again and on the truck he put both front and rear at 40 and he has reported the truck is the best it has even been. He is on the edge with these tires and I'm trying to find something better to offer as a sugestion then to repeat the same or worse go the wrong way in stability.

GM redesigned the Silverado and the Suburban in 2007. Having been a GM man before I knew well both the 1500 and 2500’s in the 1998 to 2006 vintage. GM changed the trucks in 2007 to even ride better then the 2000 to 2006 vintage. And they rode very well in the 1500’s. So these new trucks ride really nice and the tires are being matched to the suspension. I checked this week and the 2010 1500 PU's still have the Goodyear Wranger ST’s on them.

See this article off of tire rack to help with what I’m saying about tire selection, suspensions and happy customers. http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=22

As a point of reference, 3 years ago I had another buddy right here in my yard with a new 2007 1500 Suburban. It had the same design upgrades and then some as the PU’s. He had a 2004 Burb and it towed his TT fine. But this new 2007 was all over. We reset the hitch which was not right, scaled the truck and axles and everything was in line. I rode in the truck with him and I had him due a sharp S turn doing 30mph on the back roads and the truck went soggy to the point of scary. And those OEM tires where all at max side wall. So I know this tire and suspension deal has changed since my 2002 Tahoe I had. The 2007 Burb and PU I’m sure may be on different tires.

So I’m reaching out to see if anyone else has gone thru this and what tire they replaced the OEM with for better stability. Or you yourself are right now in this same issue.

Need:

· Brand, size and model of tire?
· Air pressure front and rear of truck when towing? Assuming Tt is at max cold pressure.
· Good or bad towing experiences?
· What year/model camper did you have and what type of WD hitch/anti sway did you have?
· What year and model ½ ton truck?

I checked the local Ford dealer lot and they are running Firestone Destination LE’s P265/65R18 on the 2010 F150 PU's. And they have a LT option too Goodyear Wrangler ATS LT275/65R18’s. They are not E range, I missed if the a C or D.

Any help greatly appreciated.

Thanks

John

PS And does anyone know what the brand and model tire was stock on the 2000 to 2006 1500 Suburbans/Tahoes? I can’t remember. That was my last personal ½ ton TV. Since I have been on 3/4 an 1 ton TV's which are a different animal. HenryJ do you remember yours?

[Sunline Fan]

Originally Posted by JohnB

From that end need I am reaching out to fellow Sunline owners and some input on brands/models of P tires that have been known to tow stable ideally on the newer 2007 and forward, GM 1500 PU’s. And ones that are known to have issues with too much side wall flex. We are not exactly hung up on the Chevy’s; Ford, Dodge and other brands are OK to throw in the mix as well as well as other year trucks.

Hi John,

I'm confused. Why not just move up to an LT tire? I'd think that would get much more stability over a passenger tire?

Jon

[JohnB]

Originally Posted by Sunline Fan

Hi John,

I'm confused. Why not just move up to an LT tire? I'd think that would get much more stability over a passenger tire?

Jon

Hi Jon

Looking for options. The tire and suspension need to be matched to be able to tow stable. A soft suspension needs a stiffer tire. The stiffer suspension can allow the softer tire. This is complex to sort out unless you have researched this to find someone who has a similar rig, truck and tire to know if it works.

And LT’s are a mixed bag too. Not all are created equal as I myself found that out. The LTX and my 2500 Suburban where 5 psi from being stable and not being stable.

And then which LT load range? Putting a full blown E range on a ½ ton has it’s own issue. The LT is still soggy until it gets in the higher pressure area. Like 60 and up. So now you have to run 60 to 65 psi to get stable on certian LT E ranges. My Steel Tex I could run 50 in the front and be rock solid. Just road a little rougher then the LTX.

I had a buddy here in town do this on his 2004 Yukon. I helped him with the hitch and he upgraded the tires afterwords. When he left the house his rig was the best it ever was. Then he had to change tires as the P where shot. The first trip out he went backwards on the BFG LT’s, rig all over the place, until he aired them up past 60psi. The E range allows the higher pressures to get the stiff tire but you have to run that at the higher pressure. Now comes the rims?? Can a P rated OEM rim take 80PSI? Another thing to sort thru.

Then there is the front end bounce. I myself experienced this on the LTX on the 2500 Burb. Again that was a 2003 with ¾ ton torsion bars front end. I had to raise the pressure up to 60 to get a global shift to start becoming stable. 50psi the door sticker for the weight I absolutely could not run like I did on the Steel Tex that came with it. And then the bounce. I could not run 70 psi in the front as the truck literally jumped left to right on any hard bump. Pot hole, concrete joint etc. That suspension would not allow me to run the 70 or for sure anything higher. I could only run 65. Anything below 60 was bad, anything above 68 was bad. Not a very robust window. Guys with a F250 PSD can run 75 all day long. Different truck.

Now back to the 2007 GM redesign in the 1500 Silverado. They changed the suspension from torsion bars to coil over shock. Like a McPherson strut. That again changes the game. GM reported they did that to allow the now coil springs to be better tuned to the load. And for sure it rides a heck of a lot nicer. Problem is towing. Towing TT’s we need stable to make the anti sway hitch work. So now we need to find a tire that is stiff enough to hold the truck against the softer suspension but not so stiff it makes the front end bounce as you can’t use that either…

Ford F150’s offer a LT option. I’ll have to dig up what they are. D range or less. I’m making a for sure assumption they would not go to a E load range. On the LT’s again you have to raise the pressure high enough to get the stiffness. And hopefully that is not too high to create a front end bounce that you can’t use.

It has about come to the point you find someone with a truck like you have and what tire and pressure are they running and is it stable? When I bought by 5 new ones on the F350 I did not want to change out of the Continental Conti Trac as I knew they worked at least. Tire dealer didn’t haven them in stock and wanted to sell me Michelin LTX. Ah nope, no way even though I have gobs more wheel base over the Suburban and now in 18 inch tires verses 16’s.

This is not simple when you shell out $800 to $1,000 on tires and might get worse then you are now. But being 4 psi from a stable to a not stable rig is not great either. That is right on the edge.

So I’m on the search to find out what P or LT tire has known to work on what ½ ton truck….

PS. As a reference I towed the T2499 for a short while with my 2002 Tahoe. No sway issues and I was only using a friction sway bar at first. Those P tires and that vintage torsion bar suspension worked for towing as that is a shorter wheel base then the Sileverado ext cab, short bed my buddy here in this post is using. I had them aired up to max and it worked. His 2007 Chevy PU won’t.

This is good discussion as I know we have others using 1500 trucks well within the range of the truck but they are just not as stable as they should be due to tires.

John

[henryj]

I agree with Jon. I had Wrangler ST on my 01 Silverado 1500. They were then and still are one of the poorest performers on Tirerack.com. I switched to the Yokohama H/T-S GO51 that's still #6 on Tirerack's list. I got the LT225/75R16 LRD because it was a much better match for the skinny OEM wheels. The speedo was off by 1-2 mph after the switch.

I realize a narrow tire like this isn't likely to excite someone with a P265, and I don't know what size wheel the P265 is on, but if GM is true to form it won't be a good match. However, the Yokohama is also available in LT265/75R16 LRD. In fact, the Yoko is available in a broad range of sizes and capacities.

My son also switched to the Yoko, but P235 and has been very happy with them, but he doesn't tow. He drives too fast though and the outside edges are wearing from rolling under in the corners--that's what's wrong with P series on narrow wheels and of course is magnified when towing. I've said before what a huge difference an LRD tire makes on a 1/2 ton and wouldn't hesitate recommending to anyone to toss the OEM rubber for an LRD. But I think an LRE is unnecessary on a 1/2 ton.

Henry

[henryj]

We were typing at the same time, John. Good points, all. Let me go back to my 225 LRD. This size is a perfect match for the GVWR and GAWR of a 1/2 ton and at 2335 lb. provides a safe reserve. I ran them at 55-60 psi while towing a pup. People who like fat tires aren't going to like the looks, but that's their loss. I confess to being in old farmer at heart and preferring trucks with properly sized truck tires.

Henry

[JohnB]

Henry

I figured our replies overlapped. Thanks for joining in the conversation. I hoped you would. Good points, all and now more to research thru.

I do not know what rims are stock on the 2007 redesigned PU. I would of made an assumption, maybe a bad thing though, that it would line up correctly for the P265/70R17’s they had in 2007 and are still using today in 2010 that I saw earlier this week on the GMC lot. I’ll do some digging.

I thought along the way you had a Tahoe or Yukon when you moved into the TT world. What was that setup on tires if you remember (as I don’t…) and did it provide stable towing? My 2002 Tahoe did tow stable. That was not what made me change trucks, it was rear axle and GVWR capacity that made me upgrade.

However what ever those P tires where it was on torsion bar front end suspension which is stiffer then a McPherson strut setup now used. There I could air up the front to max cold side wall pressure and not get a bouncing front end.

For us who tow TT’s it would be nice if they had a side wall stiffness rating or at least an index. It would make this a lot easier to sort thru the maze of possibilities.

Thanks

John

[henryj]

John, just a couple more comments. The only Chevy I've owned recently was the 01 Silverado. It came with P235/75R16 Wrangler ST on, I believe, 6 in. wide wheels. It was also a 2wd and had coil springs in the front. The OEM wheel size is on the door sticker of all GMs so it should be easy to get from your friend. I think for 07 it should be 17X7.5 which is actually a decent sized wheel and Tirerack says the OEM tire is a 265/70R17. This is one of half a dozen OEMs that GM shipped on this model, but they were all pretty mediocre.

For any members who aren't familiar with tirerack.com...
...you can search for the exact OEM tire, and other similar sizes, for any vehicle you want by entering the make etc. in this Tirerack page Search Tires by Vehicle

...and, on the above page, click the "survey results" button in the ribbon, then click on each category of light truck tire to see a table ranking the tires. Just above the table is an "enter tire size" option that will highlight each tire in the table that matches the truck you're researching. Click on the tire you want and then click on the "specs" tab halfway down that page to see all the sizes and their dimensions and load capacities.

John, I was checking tire sizes for your friend while I was working through the above links. The P265, with some minor brand variation, is 31.7 in tall with 660 revs/mile. Speedometers/computers can be re-programmed, but it would be simpler to get another tire with similar numbers. Often you can go down one size and up one aspect ratio and not change revs/mile. But I can't find a whole lot. I'm not flogging Yoko, but the H/T-S G051 has an interesting alternative in a P245/70R17 and a LT245/70R17 LRD. The P245 also goes to 51 psi which might be advantageous. Both of these 245's have a tread width of 7.5 in which is a perfect match for your friend's 7.5 in wheel. I'd certainly consider these alternatives for myself based on my favorable experience in going down/up from P235 to LT225, but that's a sample size of one

You're definitely right about tire selection being a risk.

Henry

[ihsolutions]

Admittedly, I have not read the entire thread, but one thought jumps out. Even my 2500HD had some front end bounce pulling my old 2570, until I changed out the OEM stocks for Bilsteins. That made a world of difference, and then some.

Right now I'm pulling a 13,000 pound loaded fifth wheel with this truck, running Michelin LTX M/S e-rated tires inflated to 80 psi. Apples and oranges, I know, but I don't see how p-rated tires would be more appropriate for towing than LT, regardless of the circumstances. Again, I have not read the entire thread.

My friend recently bought a 31' Heartland North Trail and is experiencing the exact same problems as JohnB describes pulling with his F-150. Which is what interested me in this post in the first place...

Jeff

[quaddriver]

You should have no trouble as long as you get an LT rated P-metric tire in XL load range (allows for 225/235) or an inch tire (i.e. 30-950 etc in LRC)

Dont go a load range excessively high, I had someone put E range tires on a half ton chevy and wondered why it seemed to launch at bumps...and remember when you increase diameter, the %-age you increase lowers your axle ratio (hence wheel torque) by the same amount.

no half ton pickup, loaded within limits and pulling a trailer within limits is going to dangerously flex any sidewalls.

personal prefs: if AT tread, bf goodrich trail ta(I have run these in 15 inch ford and 16 inch chevy for a couple decades using LT235 or 30-950) and for highway tread - michelin LTX MS

I have found wranglers to be lacking, but when walmart puts the 235's for $50 each its hard not to stock a few yanno?

[dkasten39828]

John, I ran Yoko's and Dunlop's on my 1/2-ton pickup. 30x9.5R15 LT (load Range C) was the size I used. I ran the rear tires at 50 PSI cold when towing... the front ones were at 45 PSI.

If I increased the pressure to 50 in the front, I got more bounce. The tires seemed to handle the road better at 45.

I towed both our popup (3000 GVWR) and a hybrid (4400 GVWR). Neither one had a heavy tongue weight.

P.S. - The Yoko's were more comfortable towing or not. I run Yoko's now on the 2500 and get between 50-60K miles on them before they're worn out.