OliverDennis52

That's likely my next move. It came with the chinese Goodride tires. I went out and checked this morning and found that both tires were overinflated by 10lbs (60lbs on a max PSI of 50). Likely overinflated while it was stored on the dealer's lot and they didn't adjust them before I drove off with it. I'm sure that extra 10lbs didn't help either. Trailer dealer was "checking" with the warranty department and I'm waiting to hear back. Trailer is a new Big Tex 30SA.

Picked up a new 5x10 utility trailer this weekend. Drove it about 100 miles to pick up an ATV. On the way, empty, it towed just fine, no issues. Once I loaded the ATV (about 700lbs) and started to drive home, I experienced some pretty significant vibrations at highway speeds, around 60-65mph. The vibration was variable and would get worse at times and then subside, but significant enough that I could see the front of the truck shake. The trailer was level and I adjusted the load a bit during the ride back to see if it was due to the weight distribution to no avail. Now I've towed other trailers with heavier loads with my truck and they were always smooth as glass, no issues. I'm not thinking it's the truck. When I got home, I raised the trailer to check the wheels and tires and found that both tires had at least 1/8 inch of run out (not round). The rims where good. When I spun the wheels you could visibly see the vertical wobble. I thought it might be flat spots, but after 200 miles those should have resolved themselves. My question is, would a 1/8 to 1/4 inch run out (both tires) cause this type of vibration? The trailer dealer is checking with the manufacturer on next steps, but looking to see if anyone else has experience here. Thanks

220/221, Whatever it takes. Sorry, couldn't help myself

Yep. Duratracs are mileage killers. I swapped mine out with a non AT P metric tire and saw a noticeable increase in MPGs.

I believe everything I read on the internet, and now I'm so confused.

Man, what a difference. Truck rides like a Cadillac now - smooth and quiet - at least compared to the Duratracs. Even my wife said she couldn't believe how much it improved. They set the tire pressure back to 41 so I lowered to 37 after it cooled down with no warning. I may go a bit closer to 35 after driving it a while and watching the pressures. Best mod so far, at least for me. Happy camper at the moment.

I have an appointment Saturday to have them installed at Discount Tire. I called and confirmed that the P metric recommended PSI is 35. They told me they could re-calibrate the TPMS for me, we'll see.

I agree with you on this one. I'm curious if anyone knows the low pressure threshold of the TPMS. I've read that it is generally 25% below the sticker rating (41 on my truck). If that's the case, that gives me a good 10lbs before it triggers a warning and I won't have to manage it. I went through the owners manual and no mention it. Not really interested in having it re-calibrated.

I'm leaning that way. These are the one's I'm looking hard at... https://www.discounttire.com/buy-tires/michelin-defender-ltx-m-s/p/27041 My Gross trailer weight will range from about 3-4K making 3 or 4 round trips each year of 200 miles through hills of PA and WV. Load rating is higher than the stock duratracs, but my only concern is the max tire pressure on the non LT Michelins is 44PSI and the truck requires 41PSI. I'm no tire expert, but is there a concern running them close to the max PSI rating?

Good point. Hadn't thought of that. Truck says 41 and the P Metric Defenders are max inflation at 44, which doesn't leave a lot of room.

Need to dump the stock duratracs. Noise is annoying, snow traction is marginal and I really don't need a mud tire for going off road. I do tow a bit but not real heavy loads, mostly pulling a John Deere Gator and firewood to camp a few times a year. Going with the Michelin Defenders but I'm not quite sure which "version" to get. Stock Duratracs are LT275/65/18 load index 113 with Q speed rating. Michelin Defenders have 2 versions in the same size 275/65/18 with load index 116 and speed rating T LT275/65/18 with load index 123/120 speed rating R Is it really necessary to go with the LT version? The non LT Michelin has a higher load rating and speed rating than the stock duratracs and are 8lbs lighter too. What am I missing? Of course, when I look on Tire Rack, they say only the LT model fits since the stock tires are LT rated.

I'm in the same ballpark, but I have an AT4 with more drag due to the lift, drive in very hilly terrain and I don't baby it. I can get close to 30 if I run it below 65mph, in the summer, flat roads, no wind and go easy on the gas pedal. But where's the fun in that. As others have said, lot's of variables, especially the right foot, will impact mileage.

Notify a staff member? https://www.gm-trucks.com/forums/staff/

Yeah, top tier Diesel is a unicorn in PA as well. Based on the website, it's either Costco or Kirkland, and neither offer it in PA at all.

Wait...there's a DEF RANGE?? I've never seen an actual range but then again I haven't got a low message yet either. Sorry, can't give you any tips or solution, but did they happen to do a software update while you were there?