Tire size?

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Dutch Rutter

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I guess there really is a significant difference on what fits a 3/4 ton versus one ton due to the frame height and axles... I have 33s and no lift and a lot of room in the fender well. I think I can fit 35's as is but I'll probably do a 2ish inch lift if I go up in tire size.

I've been thinking this same thing ^ My truck for instance has from what I can tell 2" blocks in the rear and I'm assuming longer springs in the front. Rides great with my 33x12.5x16.5 with zero rubbing whatsoever and nothing has been trimmed, shaved, cut or modified in any way and I've had it flexed to the point of picking up a tire. I think I could fit 35s with minor rubbing when turning (not that I want to)

To the OP what gearing and transmission do you have? This plays a part in what tires you can run.
 

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I've been thinking this same thing ^ My truck for instance has from what I can tell 2" blocks in the rear and I'm assuming longer springs in the front. Rides great with my 33x12.5x16.5 with zero rubbing whatsoever and nothing has been trimmed, shaved, cut or modified in any way and I've had it flexed to the point of picking up a tire. I think I could fit 35s with minor rubbing when turning (not that I want to)

To the OP what gearing and transmission do you have? This plays a part in what tires you can run.

Your spring is probably just a higher arch spring with no extra length. 33 x 12'50's fit with no lift in most cases but there are a few tires that are a combination of wider and taller than advertised that may push the limit on rubbing.
 

77 K20

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Removing the front sway bar gives you a better ride?


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Yes, it does with certain bumps anyway. Near my house is a big dip- for water to run thru a channel in the road. Before it was very rough. When I removed the sway bar the front end takes it much better now.

With a lift the sway bar angles down to the axle. When you hit a bump the axle comes upward and tries to "compress" the sway bar. This can't happen.

Instead of removing it they make a sway bar disconnect that allows the sway bar ends to pivot a bit. This supposedly makes it ride better. If you disconnect it to go offroading you get more articulation- which is a good thing but it can be very hard to get it connected again. They say you have to park somewhere perfectly level and might need a big hammer.

As an experiment I unbolted my sway bar to see how it rode. I liked it so much I didn't see the need to buy the disconnect.
 

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Yes, it does with certain bumps anyway. Near my house is a big dip- for water to run thru a channel in the road. Before it was very rough. When I removed the sway bar the front end takes it much better now.

With a lift the sway bar angles down to the axle. When you hit a bump the axle comes upward and tries to "compress" the sway bar. This can't happen.

Instead of removing it they make a sway bar disconnect that allows the sway bar ends to pivot a bit. This supposedly makes it ride better. If you disconnect it to go offroading you get more articulation- which is a good thing but it can be very hard to get it connected again. They say you have to park somewhere perfectly level and might need a big hammer.

As an experiment I unbolted my sway bar to see how it rode. I liked it so much I didn't see the need to buy the disconnect.

Interesting. That would make sense that anything other than stock angles wouldn’t be ideal, but do you lose any handling performance? Not that these trucks are built for going around corners fast...


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77 K20

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Interesting. That would make sense that anything other than stock angles wouldn’t be ideal, but do you lose any handling performance? Not that these trucks are built for going around corners fast...


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I was concerned at first it would be mushy and sway all over- but with the HD springs in the front and the stock 3/4 ton springs in the rear it doesn't lean much at all. At least nothing I'd call unsafe.

Now if I had a slide in camper or something like that it might be a completely different story.
 

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I was concerned at first it would be mushy and sway all over- but with the HD springs in the front and the stock 3/4 ton springs in the rear it doesn't lean much at all. At least nothing I'd call unsafe.

Now if I had a slide in camper or something like that it might be a completely different story.

Hmm. New swaybar bushings have been on my list but maybe I’ll try taking the sucker off first


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The general consensus is the front springs are soft, to allow for better ride quality, and that is why gm kept a sway bar on the front axle, so if you put on a lift with something that is technically stiffer then its not as harmful when you take the sway bar off but then again I think it depends on the spring maker and if it is a soft ride or not.
 

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I asked Rough Country what size tire and rim I could use on a 4inch lift 52 leaf spring and they said 35x12.5 with a 9inch wide rim with 4.5 back spacing. I don't know if they are talking 15inch rim or 16.
 

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I've been thinking this same thing ^ My truck for instance has from what I can tell 2" blocks in the rear and I'm assuming longer springs in the front. Rides great with my 33x12.5x16.5 with zero rubbing whatsoever and nothing has been trimmed, shaved, cut or modified in any way and I've had it flexed to the point of picking up a tire. I think I could fit 35s with minor rubbing when turning (not that I want to)

To the OP what gearing and transmission do you have? This plays a part in what tires you can run.
I have 4.11 gears with a 4 speed manual Trany.
 

rpcraft

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I asked Rough Country what size tire and rim I could use on a 4inch lift 52 leaf spring and they said 35x12.5 with a 9inch wide rim with 4.5 back spacing. I don't know if they are talking 15inch rim or 16.

It would not matter much with either. 4.5 inch back spacing is just about stock (I think it is stock actually) so as long as you are running half ton brakes on the front 16 and 15 inch wheels will both fit, but with 35 inch tire you probably won't find many 9 inch wide wheels. Plan on a 15 x 10 or 16 x 10 with 4.5 back spacing and you will be fine. Most places will not mount anything larger than a 33 /12.50 on a 15 x 8 just so you know.
 

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It would not matter much with either. 4.5 inch back spacing is just about stock (I think it is stock actually) so as long as you are running half ton brakes on the front 16 and 15 inch wheels will both fit, but with 35 inch tire you probably won't find many 9 inch wide wheels. Plan on a 15 x 10 or 16 x 10 with 4.5 back spacing and you will be fine. Most places will not mount anything larger than a 33 /12.50 on a 15 x 8 just so you know.
I do have a set of 16.5 inch rims. I will have to measure how wide they are but it was on the pickup before but the previous owner switch to 16 inch because he was pulling a cattle trailer with it. I won't be doing that. Do you think the 16.5's would be better. I heard it's hard to find tires for that size rim. He also had the 16.5's on there with now lift.
 

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A 16" wheel with 35" tire is a great combo for offroad while still keeping some on road manners. Plus with your gearing 35"s wont be a problem.

16.5" wheels are harder to find tires for and when you do, you don't get many options. That is what I currently have on my truck and will be going with a 16" wheel instead.
 
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I may be incorrect but I was told that 16.5's are a little harder to find oversized tires for unless you look at military take-offs. There are lots of OEM sized tires that I know of but because of that I never really looked at 16.5 as an overall option.
 

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I was looking at getting some of the Pro Comp 16 x 10 8 lug Rock Crawlers but I just realized most of them are listed as only 8 inches wide. I'm sure I can get on a phone call with one of the local places in DFW here and get some that are 16 x 10 but its not a huge issue because I'm probably just going to keep around a 33 inch tire. I'm already running some Falken Wildpeak AT 3's on my Frontier in 285/75/16. I think the next size up is a true 33 x 12.50 and they ride fantastic (very little road noise at all).
 

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I think I will keep the 16's on. Thanks for all your guys help. It's greatly appreciated.
 

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