I have a 5.0 4x4 w/3.31s and stock chrome package 18s. Everyone talks about 3.31s don't have power and we can't add bigger tires without it being slow and not being able to tow. Always thought this wasn't true, but now I'm starting to believe it.

About to get new tires with a leveling kit, and I was going to go a size bigger with 20s (275/60r20) so I can stay with P rated tires. But now I'm leaning towards keeping the stock wheels, getting an A/T stock tire size and calling it a day. I save a ton of money, and my 3.31s keep doing what they are good at... getting me good mpg. I average 19 mpg with 50 city/50 highway, and on road trips I get between 22-23 mpg.

Thoughts?

 

A/T tires may add some weight as well, so be aware of that. I noticed a little difference with my 3.55s going to 20'' wheels and BFG KO2 33s. But not that much. I am glad I went with 3.55s when building mine.

 

What is your stock tire size? The larger size you listed (275/55/20) is my stock tire size which happens to be about the same overall size as the 18's on my 2011 (275/65/18).

As for going to an AT, if you stay with a P-Rated AT you probably won't add much weight. If you go to an LT you will probably end up heavier than a P-rated tire on 20's.

 

Getting a new set of stock sized tires? I fail to understand how this is unthinkable...

 

The twankies wif stock tire size ( 275/55/20) are 31.9" diameter. What are yours currently?

IF the diameter remains the same you are looking at wheel weight difference only (NO effective gearing change) - so a slight increase in static mass and rotational inertia - likely not enough to concern yerself with.

MGD

 

Sorry about that, edited my post. I meant 275/60r20.

I will definitely stay with P rated tires.

Current size is 275/65r18 (32.1" x 10.8")

 

Do some research on the specific tires you are looking at and their weights. Generally speaking, you are going to gain about 3-5lbs a tire going from the stockers to p-rated AT tires. P-Rated At's are heavier than what you have and LT's a heavier yet.

As an example (Sorry they are 17", but it is what I am searching for)
Toyo AT II's 285/70/17
P-rated 48lbs
LT 56lbs
"Extreme 285/75/17" (LT as well) 63 lbs

You can also see a big difference in weight when you go between certain sizes. in the Toyo AT, there is a big jump when you increase the width beyond 295mm.

 

I'm aware of this, but the A/T adding a couple pounds is worth the trade off for me.

The only way to actually go bigger would to add LT (lots of weight) or go 20s with a P rated tire (also a lot of weight going to 20s)

 

Here I thought you were going to say you were about to brush paint your truck or something

 

I think you are confused. The stock size is probably 275/55/20.



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