Tire time need thoughts on slight size change

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SirRobyn0

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Ok so my 1984 C20 currently has 235/85R16 open country AT tires on it. When I bought it a year and half ago these tires were on it and have plenty of tread but I'm noticing cracks so it's time. I want and will only run 10 ply E rated tires. I haul with the truck and sometimes when I do feed runs I can be driving 100 miles in combination of freeway and country roads. On these runs I'm often loaded over a ton, plus I have a 18 foot open trailer that I tow with it occasionally. So I need good tires that'll handle the stress, plus here on the farm I need tires that will grip when I'm out in the fields, that can involve grass or light mud.

So a few years ago I was given 6 new 225/75R16 Goodyear Workhorse Extra Grip studded tires E rated. I took them because my Jeep runs 235/70R16 so I have 4 or those that I use on the Jeep for winter / snow / ice ect, but because the Jeep is an AWD I'll never be able to use 2 of those tires. Which leads me to want to use those two studded tires on the truck.

In my mind I have a couple of choices. I can stay with the stock 235/85R16 after all that's what GM says the truck should have. But I'm still rockin' the 3.41 rear end so a little shorter tire would raise my RPM a tiny bit, roughly 100 RPM, so probably not enough to make much of a difference, and a re-gear is in the future so there is that. Also a shorter tire will put the truck a tiny bit lower to the ground which I would like.

So my Alternate tire size choices would be 245/75R16, this would put the truck roughly 3/4 of an inch closer to the ground, but the tire would be 3/8" wider, also this tire is available in my favorite tire the General Grabber AT2 E rated of course. The tire chains I bought to fit the stock size tires will fit these no problem, but running the 2 studded 225/75R16s on the back might look a little odd. So in that combination I'd be pretty much forgetting about the studs, or only putting them on when snow is forecast.

The other alternate would be to buy 4 225/75R16 tires, this would put the truck roughly 1 3/8" of an inch closer to the ground, but the tire would be almost 1/2" narrower. I'd need to buy new tire chains, but the studded tires I currently own are the same size. Concerned that the narrower tire might make it less stable when hauling a load, or towing. And also concerned if they would simply look to small on the truck. Also E-rated Grabber is not available in this size, so I'd have to get my second favorite tire the Falken Wildpeak AT3W, which is a little cheaper but only $10 each so not really a factor.

Frankly writing this all out I think I see what the best choice is, but I'd still like opinions, particularly if you have run any of these sizes.
 

75gmck25

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I use 245/75R16 E rated tires because they are a very common size for 3/4 ton trucks. You can find almost all major truck tires in that size, and with E load rating. Being a common size usually means they are a volume seller, and a little cheaper. Even Walmart carries them.

The 235/85R16E might actually be closer in diameter to the original 9.50-16.5 tires that came on my truck, but I like the looks of the slightly wider 245 tire.

Bruce
 

BKING33

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Just remember you are going to lose some hauling capacity. Your going from a tire with a 3042lb max load to a tire with 2680lb if you drop to the 225.
 

bucket

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I don't like any of the options, lol.

I'd go with a 285/75/16. Wider and taller. From personal experience, it helps with traction on soft ground and actually improves towing comfort greatly. No more swaying, it feels just plain stable as can be.
 

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The BFG T/A KO would be suitable, and it's one of the shorter rugs too.
I don't like any of the options, lol.

I'd go with a 285/75/16. Wider and taller. From personal experience, it helps with traction on soft ground and actually improves towing comfort greatly. No more swaying, it feels just plain stable as can be.

I would have to agree, he did say he needed traction on the farm. Taller is better for that.
Well he's just going to have to re-gear then. And I think he should drop in a BB too. If he already has that then at least stroke it to 496.
 

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If you have used this before, the link lets you visually see the difference in tire size.

https://tiresize.com/comparison/

My taste is a 265/75R16, but if you want to lower it then the 245/75R16. Both of these tires are easier to get at a tire shop. I think the 225 would look to short.
 

SirRobyn0

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I appreciate everyone's advise. @shiftpro Yes I need to get off the pot and do the regear. I'd prefer an AT to TA, and I use to use the BFG AT KO, but after discovering General AT2 I'll never go back. If you'd like to ship me that 496 BB I'll do the install :):)

@75gmck25 the 235/85R16 is the recommended replacement for the 16.5 I'm pretty sure by 1984 they were rolling out of the factory with 235/85R16. While I will be ordering my set of tires online I really want it to be size that is easily found at a tire store, should I have a sudden need for a replacement tire while out of town in the truck. @BKING33 good point. And actually as I was looking what I wrote I was leaning away from the 225's that and @Craig 85 comment about looks, I'm throwing out the 225's. @bucket and everyone else that suggested something even wider than the 245's. I'll look at 265's and 285's tonight online and think about that option. What do you guys think about 245/75R16's on the front and running either 265's or 285's on the back. Obviously no rotating the tires at that point, but maybe I'd get a little increase in traction on the farm, without increasing the rolling resistance on the front. Keep in mind my rig is a RWD.
 

bucket

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I've run the stock 9.50x16.5's all around, I've run them just on the front with 33x12.5x16.5's on the rear and I've run 285/75/16's all around.

I didn't like the stock setup at all, it was just like the 235/85's on my old C20 that I didn't care for either.

Having the stock tires up front and the bigger tires out back helped tremendously with traction and towing, but the skinny fronts still had a tendency to plow while trying to turn on soft ground. They also were easy to lock up under braking when towing in wet weather.

Having the 285's all around is the bee's knees. Better traction, better towing stability and more rubber on the ground for braking.

Through all of my various wheel/tire setups (there have been more, lol) I have not noticed any difference in fuel economy. That's with mpg figures based off of gps miles, rather than the odo.
 

SirRobyn0

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I've run the stock 9.50x16.5's all around, I've run them just on the front with 33x12.5x16.5's on the rear and I've run 285/75/16's all around.

I didn't like the stock setup at all, it was just like the 235/85's on my old C20 that I didn't care for either.

Having the stock tires up front and the bigger tires out back helped tremendously with traction and towing, but the skinny fronts still had a tendency to plow while trying to turn on soft ground. They also were easy to lock up under braking when towing in wet weather.

Having the 285's all around is the bee's knees. Better traction, better towing stability and more rubber on the ground for braking.

Through all of my various wheel/tire setups (there have been more, lol) I have not noticed any difference in fuel economy. That's with mpg figures based off of gps miles, rather than the odo.

Good info thanks. 265/75R16 General Grabber AT are available E rated for 3,415 LBS at the same price as the 245/75R16 Grabber AT E rated but at 3,085 LBS so the picture is getting clearer. Grabber AT is not available in 285, but the Falken AT3W is. According to tiresize.com calculator the 265/75R16 is .1" shorter and 1.2" wider than factory 235/85R16, my current tire chains are listed to fit the 265's. The 285/75R16 is .4" taller and 1.9" wider than factory, my current tire chains are not listed to fit these tires. Based height, not being able to get the grabber, and my chains not work with the 285's I think at this point it's between 265/75R16 and 245/75R16, but I will say I think I'm leaning towards the 265s now. Before someone suggests getting a 285/70R16 to reduce the height that is also out because that size and even more over in an E-rated is rare bird and I would like to stay with something that is fairly easy to find in a pinch. Thanks for the thoughts so far.
 

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Those 225 pizza cutters are basically a specialty tire used primarily for delivery trucks and the only box they check for you is the lower ride height.
235-85, 245-75 and 265-75, all would work just fine.
 

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I know your talking size,but I would recommend Nitto’s ridge grappler.Load range F.Good hwy manners and decent traction.
 

SirRobyn0

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@BKING33 Thanks for the pic. As it turns out I had a 77 C20 dropped off at the shop this morning and it just so happen to have 265/75R16's on it. They look good. I was just looking at some tire recommendation charts. The stock wheels are 6.5 inches wide. The 265/75R16's are recommended for 7.0 - 8.0 inch rims and 285/75R16 are recommended for 7.5 - 9.0 inch rims. From my experiance those charts are guilds not rules so I'm comfortable with 265's, but I think the 285's are a touch wide for the factory rims.

Given all that I think I'm headed for 265/75R16's, BTW @Grit dog the 225/75R16's were common on the 3/4 and 1 ton Dodge vans from the early 90's to the end of production.

@Curt Thanks for the recommendation, I'm pretty set in what I like for tires, but when I have a little more time I'll look up the grappler.
 

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Just put on a set of NITTO Terra Grappler LT285/75R17 and they are a tad tall for the rear of the front fenders...: ( But I still like them.

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The brakes are Hummer with 4 puck calipers which required larger wheels from factory. I'm still thinking on what I am going to do with the fenders......lift, cut, body lift.......suggestions?
 

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