How much will my gas mileage decrease by adding bigger tires? Say I have 18 inch stock tires on there and then I put on 30 inch mud tires (Or at least tires that have a better pattern on them that could get a better grip in the mud) then how much would the gas mileage decrease? (Idk if I would end up getting that big of tires, but I was trying to base it off of something, I might get bigger or smaller tires than that, I really am not sure yet, because that is later on down the road more than likely, but I am just trying to get a general idea.

Thanks, Tyler.

 

I had a chevy pickup a couple years ago with stock tires 235/75R15's mud terrain tires and i was getting 15-16 mpg. When those tires were bald i put on 31 10.50's mud terrains and i was getting 11 mpg. I was pissed. But hey my 71 has a 460, 38.5" mickey thompson baja claws and 5.13 gears i get 5mpg and i love every bit of it.

 

You will get a decrease in perceived mpg due to the size difference of the tires. If you go from a 28" diameter tire to a 30" tire, you will go 30 miles when your odo indicates 28 miles. So you will need to correct your gas mileage calculations for that. If you go a lot bigger than stock, your gearing will end up being too high and your engine will lug. And you'll be into the gas pedal more, so that will cut mileage.

You will also probably get a reduction in real mpg, after correcting for the math, because the mudders will weigh more (so they will use more power to get them spinning when you accelerate) and the mud tread pattern will generally "scrub" the pavement more with the blocks flexing and stuff, so you'll be using more gas flexing the rubber. If you stay with the same size and move from a street tread to a mud tread, I'm guessing you're gonna lose 2 mpg or so.

It all depends on how extreme you go, but you will get a decrease in mileage.

George

 

Alright, thanks. Well, I have not decide if im going to go all out and get extremley nice mud tires or something that is sort of in batween. So that leads me to my next question. If I am going to change my tires say from stock 18" to 30" mud tires then is there any conversion kit that I will need? And when it comes to changing my gearing what all exactly will I have to change? Like which gears specificly and to approx what ratio?

If you have complete mud tires like nitto mud grapplers then will the tread wear out extremley fast on the pavement?

Lol Hanker, I have a friend who has an older chevy 2500 with a 350 in it and he gets 6 mpg. He has big *** mud tires on it though and a bunch of stuff done to it.

 

What do you mean by 18" tires? Is this wheel size?

Measure the outside diameter of the tires you now have, or look that up, and then find the actual diameter of what you're gonna put on there. Only then will you know what you're actually up against.

If you upsize tires, you will have to change speedometer programming or gearing if you want the speedo to be accurate.

If you really upsize tires a lot, you will probably want to change axle gears, and that will be a grand or more for two axles. You are giving us zero information as to what tires you now have and what tires you want, and what gear ratio you already have, so guessing at a new gear ratio is impossible.

I would humbly suggest you do some Internet surfing, or go talk to guys at tire stores, and nail down what you really want so that you can put it into understandable terms.

Good luck,
George

 

I also have one last section of questions for you nice people lol. 1. How much of a difference will mud tires like these: Nitto Tire - High Performance Tires for Car and Truck Enthusiasts make a difference in the mud compared to just a regular set of stock tires from like goodrich or something?

2. And if i'm going to get big tires then do I have to have a lift?

3. What is generally the purpose of a lift? I know the look amazing lol, so I will probably get one regardless, but I was just curious what the actual reasoning was.

4. One of my friends has "wider" tires on his truck that sort of stick out on the sides some kind of like how these two tires put together do, but instead of two it only sticks out about maybe 1-2 inches: http://images.truckinweb.com/events/...wide_tires.jpg And I personally think it looks good, but is it the tires he got that did that, or did he do something to his axle ect?

5. Do bigger tires actually help you in the mud or are they just for looks?

6. What about wider tires?

7. How rough does it get on the street with mud tires such as the nitto mud grapplers? It says on there ride comfort is really low lol. I was just wondering, will it be like bump bump bump bump bump bump type of thing or will it not be a huge noticeable difference compared to stock tires?

8. Also, Hanker, with your chevy pickup what size engine did you have in it?

9. What will the tread life of a mud tire be compared to a normal street made tire? (Idk what the tread life of a normal tire is, so please informe me )

10. This truck (Chevy silverado 2003, 1500, with a small v8 or a v6, will also be my everyday driver on top of mud/play truck, so this is why I am asking how quick the wear will be on a mud tire if actually driven on the street more than the mud)

11. Last and final question, what is the different ways to lift a truck and what are the advantages/gains from it? (I think it is just suspension lift and body lift, am I correct or off?)

 

When I say 18" I mean eighteen inch tires, like the size. I am fairly new to vehicles (I'm 16) But I am trying to learn more about them. Okay, I just found out and here is the tires on it: 235/75SR16.0 So those are the tires that I now have and I am honestly not sure what tires I want right now, if you read my above post and reply to that then I will be able to look through some tires and tell you.

I do not know what the gearing is in it, I looked it up on the internet and couldnt find it either on google. I know it is stock gearing and it is a 2003 Chevy silverado, 1500, 4wd, either the v6 or a small v8 is what my dad said, but he is unsure at the moment.

So from those tires and knowing the information I have given you (Pretty much all I know about it right now because we are not buying it for another week or two) then what would you say around the highest tires size is that I can get with out having to changing the axle gears or something along those lines that will cost 1k +? (If possible just make a estimate, because that is all I am looking for to get a general idea to start looking and then once I actually have the truck I will find out more information.)

Thank you very much!!
Tyler.

 

I think you need to drive the truck stock for a while and learn a bunch more before you go anywhere with changing things around. A 235/75x16" tire is a little shy of 30 inches tall. Where the heck did you get 18"? It is very difficult to answer questions for someone who does not speak the same language, or who does not even know what question he is asking.

If you are not even aware of what engine you have, you should not spend`any money making modifications or changing tires yet. Open the hood and count spark plugs or something. Check the VIN plate engine code against some lists. I think at this point you should just drive the truck and spend your time learning. If you want to learn about mudding, go mudding with some friends or something and talk to them, see what works, etc. It will cost a bunch of money once you start changing stuff on a truck, and broken parts from mudding or four wheeling will surely break your budget.

Although tires are the same whether you're talking Ford or Chevy, you may want to find a Chevy forum where, if you have other mechanical type questions about your truck, you can get better answers.

Do some searches and spend a few months reading forum threads, and you will start learning about trucks. If you have questions, make sure they are specific enough that someone can answer them. I intend no offense, but you cannot expect people on a forum like this to spoon feed you a complete education.

Good luck,
George

ps for a cheap approach to mudding that is good for you, get a mountain bike...that's my approach.

 

No, I know trucks fairly well, you just do not understand what I mean. My dad use to be a mechanic.. I do NOT have the truck yet and we have NOT even looked at it personally yet and it is a little old lady who owns it who does NOT know what engine is even in it, so it is kind of hard to know with out looking. I have been driving a chevy 2500 with a 6.0 V8 vortec for about 4 months and ive been working on itand it has 18" tires, so I was assuming the 1500 would be the same.

 

PS I have 3 dirt bikes, a ranger, and a 4 wheeler, so I know, but could you please just try and answer some of the questions that I listed out in a line? Thanks, Tyler.

 

If your dad is a mechanic, why can you not just ask him your questions? Fathers are the best mentors...

When we talk about tires, we typically refer to the outside diameter--or at least the size, not the rim size. An 18" rim tire on a ricer is a bit different from an 18" rim tire on a truck...

Good luck,
George

 

to answer you question my truck was a 93 c1500 2wd. It had a 4.3 liter v6 in it, with a 4L60E transmission and 3.42 gears. Bone stock. when i got the truck it had 176,000 miles on it and i did a complete tune up on it and when it gave it to my sister it had 227,000 miles on it still going strong. I am a mechanic so i know how to take care of a vehicle and everytime i got it smogged the guys couldn't believe how clean it was. I put the 31.50's mud terrain tires on it at about 200,000 miles. Even though that truck was 2wd it took me anywhere i needed to go, playing in a creek, pushing 2 feet of snow, or playing in the mud on my dad's ranch. A good set of tires can really help out. But my gas mileage went down too. Its usually a good idea to use gear down your axles (using numerically higher gears) as tire size increases, otherwise your motor lugs, and that robs mpgs. But alot of things are compromise.

 

also a 2500 chevy is a 3/4 ton and that will have 6 lug 16" rims, mine was a 1500 1/2 ton and it had 5 lug 15" rims. my brother in law has a 1995 gmc 2500 4x4, with a 350 tbi and we just put 31 10.50 cooper all terrains on it and he gets 15 mpg, but 4x4 trucks have different gears, his is a Z71 and those have 3.73 gears, so it works perfect with
31's. sorry bout all the chevy stuff, i feel dirty....

 

Haha. Okay, thanks for your help, it is much appriceated. George, because my dad currently owns his own bussiness and is litterally like never home, so it's hard for him to help/show me when he is never here.