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Tire time need thoughts on slight size change

Discussion in 'Wheels and Tires' started by SirRobyn0, Mar 21, 2021.

  1. SirRobyn0

    SirRobyn0 Full Access Member

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    No beat horses here, I find this discussion very interesting. Just for anyone wondering a 33X10.5R15 converted to 16" metric would be 267/81R16 Making the 265/75R16 a about an inch shorter, but within .1" of same width, while the 285/75R16 is basically the same height but is almost 3/4" wider.
     
  2. SirRobyn0

    SirRobyn0 Full Access Member

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    I didn't get a chance to punch this one in before I left work. But a 31X10.5R15 converted to 16" metric is a 266/73R16 so a 265/75R16 is 1/2" taller than the 31X10.5R15 and .1 inches narrower. All of these figures are from tiresize.com/calculator
     
  3. bucket

    bucket Super Moderator Staff Member

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    I run ours at 50 front and 80 rear on our '00 2500 Burb at all times and it works well for us. On my '78, I ran 50/65 due to the lower rated BFG's on the '99-up aluminum wheels and I really liked that too.
     
  4. SirRobyn0

    SirRobyn0 Full Access Member

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    Tire pressure that should be another interesting conversation. So I've been running 60 front / 80 rear all times, I'd probably like to air down the rear when empty for improved ride, but I spend so much time loaded I'd be constantly airing up and down so I have been just leaving them at 80. One thing I've always wondered about, tire pressures are checked cold I think we all know that, what about loaded vs empty. At the shop I've observed, and this depends on the weight of the vehicle but if check the tire pressures on the hoist and then put the vehicle down the weight will increase the tire pressure by 2 -5 PSI. So what happens when I slap a ton of feed in the bed? Or when I'm really bad and get gravel. I'm sure the pressure goes up, but I've never checked. I've never heard a tire manufacture mention this so I assume, that as long as the tire itself is not overloaded, that it's designed to take this increase in pressure, but also wonder if anyone else ever thinks about that.
     
  5. Rusty Nail

    Rusty Nail Victim of Culture

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    Tire pressure debates sure tend to get - heated...count me in! :mad:
     
  6. BKING33

    BKING33 Full Access Member

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    I keep all my tires at 45psi for daily driving. I add 10-15 psi in rear tires when loaded. I don't tow anything heavy with it, so i never air them up to max 80 psi.
    I use my truck for heavy stuff.
     
  7. SirRobyn0

    SirRobyn0 Full Access Member

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    I was actually just looking at my door sticker and it say 50 front 80 rear, so I may try running the front at 50 with the new tires and see how I like it.
     
  8. SirRobyn0

    SirRobyn0 Full Access Member

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    Ok here it is. I think I've make my decision. I'm not comfortable going to 285/75R16 for 2 reasons. One is it'll increase my ride height, two is rim width. I know @bucket has said that it would work just fine, but I've had tires wear in the center on my Dodge Dakota for this exact reason. And if that were to start to happen I'd be stuck with it and reduced traction because I'm not going to air down, drive to where I'm picking up feed which is about 100 miles and then air up. I have no doubt that I would have a very good chance of them working out just fine, I just don't want to take the chance.

    Last night and this morning I just about had myself convinced that I'd like to put 245/75R16's on the front and 265/75R16's on the back. My reasoning is that my Dakota has 215/75R15s on the front and 235/75R15's on the back and I like the look. Then I thought about why I did that. I did it because the 235's would hit when turning. And I've had problems with the front plowing when trying to turn on softer ground. So that did that in.

    So unless someone says something earth shattering to me between now and tonight I'll be ordering a set of 4 265/75R16's, that'll be a little more than an inch wider than factory and about the same height. That way I can get some benefits of the wider tire, without having to go taller, and still be a comfortable width for me.

    Thanks for all the input guys. I'll be sure to post pics once they are installed.
     
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  9. bucket

    bucket Super Moderator Staff Member

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    Eh, I wouldn't let your findings with a lighter weight Dakota sway you. I've ran 3 sets of 285's on 6.5" rims on Suburbans and they wear evenly across. And I know oodles of other people have done the same with the GMT800 trucks.

    But really, the 265 tire should serve your purposes well and that's a fine choice too.
     
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  10. SirRobyn0

    SirRobyn0 Full Access Member

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    I have no doubt that you are right. It's a personal hang up lol. I figure the 265's will be over an inch wider than my current tires, and well if I like them maybe I'll move up to the 285's next time. Also not being able to get E-rated Grabber AT's in 285. I've had a lot of different rigs, with grabbers on it from SUV's to the Dakota for a lot of years, so I'm pretty well sold on them as being the right tire for me.
     
    Last edited: Mar 26, 2021
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  11. SirRobyn0

    SirRobyn0 Full Access Member

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    Well I ordered the tires on the 26th and they came into the shop this morning at about 9AM. I wasn't expecting them until next week. This is my last day at the shop this week, so I thought great I'll get them on the truck this afternoon. NOOOO, that was not to be. Shit hit the fan right after that and I spent pretty much the rest of the day putting out fires. No time for me, but that's the way it goes I guess. If I get into the city in the next 4 days I'll install them sooner otherwise it'll probably be Monday or Tuesday. All I had the time to do what to roll one out up against the truck. They going to look great, and I know I'll love having the General's on it. Should have taken a pic while I had it out at the truck at least, but I'll be sure to snap a few after the install.
     
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  12. SirRobyn0

    SirRobyn0 Full Access Member

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    finally today was the day, but only because I made the time for it to happen. First some pictures there will be multiple posts for all of them. Did ya hear that @Rusty Nail, so many pictures I have to do multiple posts, does this thread still suck.... NO!

    Anyhow after the pictures then I'll talk about the tires and what I think so far.

    First pic. the old Toyo open country A/T, I never liked them, but they had tread so I wanted to use them. Now they have cracks in the tread so they need to be replaced. Time to get my favorite tires on the truck the General Grabber A/T 20210407_075358.jpg


    I've just installed the first new tire on the wheel.
    20210407_074259.jpg


    New tire on the truck. Looking better already!
    20210407_130240.jpg



    New tire on the front, old one on the rear just for contrast, I should have put the hub cap back on for the pic but you get the idea. 20210407_075348.jpg


    Plenty of fender spacing even in a turn.
    20210407_134053.jpg
     
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  13. SirRobyn0

    SirRobyn0 Full Access Member

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    Looking good with 4 new tires. Unfortunately it turned overcast and rather dark out today, so it's hard to see the tread in the pictures, but you can really see them in person and makes the truck look much more rugged and work ready.


    20210407_134040.jpg 20210407_165952.jpg

    Gonna be a little bit before I can do a post with what I think of the change, but it'll happen before I go to bed tonight.
     
    Last edited: Apr 8, 2021
  14. SirRobyn0

    SirRobyn0 Full Access Member

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    Now what I think. I think the tires look great. I went from 235/85R16 to 265/75R16 both are 10 ply E rated tires, and the new tires are slightly shorter, less than a 1/4" shorter than the old tires, but are just a hair more than an inch wider. There is plenty of clearance on the front for turning. The new tires have a higher weight rating than the old, but both are E-rated. Traction wise the difference so far has been substantial, which having had grabbers in the past on other truck I expected. I haven't had them around the fields in the farm yet, but the freeway on ramp I take every afternoon I'd struggle to keep traction while accelerating with the Toyo's in the rain, today I floored it, in the rain with no issues. No noticeable changes in power from the larger foot print either. The only concern I have right now is that the truck seemed more floaty in the rear at high speed, but I was only on the highway for the last mile of the highway, so that's just not really a good test anyway. Tomorrow I'll have a much better highway run in the evening so I'll know then if this is an actual issue. I've never had this effect on other rigs that I've had grabbers on before so right now I'm thinking it might have just been in my head, and of course tires do have a short breakin period when they are new so it could have been that. so I will report back on that tomorrow night.

    Assuming the highway drive tomorrow goes well I can only see positives in this change both going to a better allterrian tire, and a wider one.
     
    Last edited: Apr 8, 2021
  15. idahovette

    idahovette Full Access Member

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    @SirRobyn0 I thought you were going to 265/75R16, or am I confused as always???!!!
     

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