I have the 4.9 with 3.08 but I'll be swapping in 3.55s if I go with 33s before the end of summer.

 

With that combo, I suggest leaning even more towards something like 31's I have a 351W with 33's and 3.55 gearing, and it can be a real dog sometimes, which is why I am planning on swapping to 4.10 of 4.56 gearing soon. I think a set of 31x10.5R15's as well as the gear swap to 3.55's would be a nice combo for your truck. I know that's what I would do.

 

I know in the end 31s would probably be the best decision, though I really like the look of 33s on our trucks.

 

i have 32 11.5s on my truck right now and do you think i will see much of a difference in power and what not if i go to a 33 10.5?

 

You wont see much of a difference in performance. You will only drop ~100 rpm at cruising speed. I would suggest a gear swap sometime in the future though either way. I am leaning towards 4.10's using stock axles that came with that gearing. May be a little hard to find, but it will be the cheapest and easiest way to do it.

 

I still don't understand how tires make that big of a difference in power like everyone says. I only drive to work, about 5 miles down the road, and I pull a small boat trailer to the lake about 25 miles.

 

right now I'm running around 1600-1700 rpm at 55 is that normal or low?

 

I'm gonna see if I can do my best to explain here. Bear with me.

Stock setup for my truck was ~29.5 inch tires and 3.55 gearing.

@55 MPH that puts the RPM at about 1599 RPM in overdrive.

With the 33's and the stock 3.55 gears:

@55 MPH that puts the RPM at about 1400 RPM.

While that may not seem like a big difference, the power band of my engine is from starts at ~1500 RPM. Because of my larger tires, at cruising speed the truck isn't in the powerband, and therefore when I come upon a hill the engine has to work considerably harder using more fuel to go up that hill. In my case, it likes to drop out of overdrive on every incline I come upon. Because of this, I usually drive with overdrive locked out when I am going under 60 MPH. Keeps the engine right in the powerband, and doesn't bog down at all. Truck just generally seems much happier out of overdrive. When I get to ~65 MPH I will go ahead and let it go into overdrive where it seems to be happy.

So essentially, it is all about keeping the truck in its powerband as to not put undo stress on the engine.

 

That's about stock. Is that in overdrive?

 

That's valid, I have a 5 speed so I'm used to dropping gear to pass. That and the 4.9 doesn't really have much of a usable power band anyway, it pulls better for me in lower rpms.

 

if your truck is a stock height 2wd even 30s will rub if for say you park on a hill so the truck leans and you crank it try to turn in a tight spot, i was going to try and re align my drooped bumper to see if that helped but it started snowing so i cant tell you

 

i wouldnt say that. it has a diesel like rpm and look at how useable a diesel. you just gotta keep the rpms low or if towing keep em up and let it bog down a little bit to its powerband

 

So are you saying go with the 33s?

 

no you have 3.08s already adding 33s would be a dog, i would go with 30s or 31s. i personally run mastercraft courser tires in 265.75 r15s which come out to about 30.6 inches and they rub, i have to try realigning my front bumper to see if that helps and if not i will have to space it out

 

Are you stock height and do you have pics of how your truck looks with that size tire? I'm just afraid I won't be able to tell a difference in size when I go to 31s.