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Want bigger tires but don't want to cut the fenders

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big blue goes 4x4

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Want bigger tires but don't want to cut the fenders
I have a '82 C30 body on a '87 V30 frame. I would really like to put bigger tires on it to help my mpg. 4.56 gear ratio isn't to bad with the 4L80e 12mpg. Cutting the fenders is not an option for me. How big can I go without rubbing? Forgot about the 3" body lift. It has one.
 
big blue goes 4x4 said:
Want bigger tires but don't want to cut the fenders
I have a '82 C30 body on a '87 V30 frame. I would really like to put bigger tires on it to help my mpg. 4.56 gear ratio isn't to bad with the 4L80e 12mpg. Cutting the fenders is not an option for me. How big can I go without rubbing? Forgot about the 3" body lift. It has one.
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Fuel economy is not an option either. Since you didn't mention the suspension I'm guessing its stock, in which case you probably could run 35" tires with a 3" body lift.
 
big blue goes 4x4 said:
why don't you think mpg will improve?
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Because the only thing bigger tires will do is add rotational mass that is harder to get going, keep going at a steady pace, and slow down.

If you want to save on fuel, re-gear to 3.73's and put smaller tires on, shedding some rotational mass.
 
The bigger tires altering the gears will help highway. They will hurt town but you'd probably be back to stock with 35's and 4.56's, or close. What rpm are you spinning at on the highway?
 
What kind of tires do you have now and what size are they? If you are looking for fuel economy, use skinny radials - something with a really lame street tread - and keep the air pressure high. I don't know if I've ever seen a chart of rolling resistance for different truck tires, but it might be good to research.

With only 3", a 35x12.5 is pushing it. You might think about a 1" zero-rate at all corners. Maybe you can find a decent 35x10.5 which should fit and give good fuel economy.

A 4.56 gear is really good with 35's and 37's
 
they are wrangler 30" overall, I believe. I've been look at the 315 75 16's 34.5 usually. If they are going to rub, then I'll go with 33's. I don't want to make a mistake and get the wronge one's $$$. In town and towing I'm not worried about mpg. It will always be crap. Highway, is important because I load and use it for work every day. 50 miles is not unheard of, in order to get to the jobs sites.
 
big blue goes 4x4 said:
they are wrangler 30" overall, I believe. I've been look at the 315 75 16's 34.5 usually. If they are going to rub, then I'll go with 33's. I don't want to make a mistake and get the wronge one's $$$. In town and towing I'm not worried about mpg. It will always be crap. Highway, is important because I load and use it for work every day. 50 miles is not unheard of, in order to get to the jobs sites.
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Well you definatly wanna go for those bigger tires then. Highway they will help MPG's. The skinnier the better for efficiency.

TSL makes SSR radials that are 35x10.5
 
those are 35.3 overall which is fine. I just don't know if they will rub. it's a little aggressive for sand down hear. I have found that an A/T works better in sugar sand grip not dig.
 
big blue goes 4x4 said:
those are 35.3 overall which is fine. I just don't know if they will rub. it's a little aggressive for sand down hear. I have found that an A/T works better in sugar sand grip not dig.
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Lol nothing works good in sugar sand except airing down IMO. If they rub its not hard to get 2in of lift for $150 without changing any major suspension componants. Shackles and zero rates...
 
I have 8" lift and 35's and can get the front tires to rub pretty easily.
 
True, that's no lie. How can I find out if they are going rub before I buy. Some one has to know for sure. Kuz your right if they are to big it could cost me.
 
2,600 rpm cruising on the highway is a little on the high side if you are interested in fuel economy, and yes larger tires will bring the rpm down for the same speed. The problem is that while the larger tires will help fuel economy on one side by bringing the rpm down, any gains are at least partially offset because of several other factors including more rolling resistance and heavier rotational masss.

For tires I would probably recommend something like a 255/85R16, about a 33x10.50, or a 285/75R16, about a 33x11.50. That size obviously won't make as much difference as a 35" tire but they would be cheaper, no fitment issues, and have less potential drawbacks effecting fuel economy.

Of course one of the best things you could do is get rid of the 3" body lift, especially since you obviously don't need the tire clearance in the current setup. Loosing the lift and the 255/85 tires would probably be the best combination.

Also, keep in mind that if you are factoring MPG based off the odometer reading it will be off with the different size tires unless you recalibrate your speedo (it may be off now).
 
8in and 35's is rediculous. I run 4in and 36x12.5s and barely rub them flexed good turning.

You can run 33's stock suspension. 35's and 3in body lift should be fine. Its not like your building a rock crawler. Its a DD correct?
 
Daily Driver sorry. Ya but I use it hard. 3000lbs in the back regularly and a 10,000lb dump trailer. I get on it at the job sites. Trails every once in a while. If i find a hill I'll clime it just because there are few and far between here. Not like back home in the mountains.
 
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