I have the Superduty Lariat Package with 4.30 gears with the LS in the back. Would it be beneficial to put on bigger tires? I have the 265's on there now...I would like to put on some 33s. Help would be appreciated...thanks.

Shawn

 

I guess it would depend on what you mean by "beneficial"!! I always think bigger tires "look" better but, milage, performance and sometimes driveablility can go right down the tubes.

 

I agree. I know that bigger tires will look better and get me a little higher. But Id like to know if engine power will be decreased because of the bigger tires. I had an 88 bronco that I stuck 31s on and it did suffer a little. it 3.55s in the axles..My superduty has 4.30. so I would think that it would not degrade to much, especcially with the v-10. Thanks.

 

Ok, this is all going on hearsay because I have a diesel and I don't know the V10 and I've also only got the 265 tires. But from others that have added larger tires up to a 35, yes you can add them. They said the engine performance was the same, mpg tended to drop, speedometer was off. If you go with 35's you could be looking at adding some kind of spacer because the tires tended to rub the springs when sharp turning. Also you need to watch how wide the new tires are or you may need some kind of fender trim added just so your truck looks right. Lifting blocks will add height but not help with the tires rubbing on the springs. Also adding a Superchips chip will improve engine performance. So if those tires did rob some of your HP/torque you would gain it back with the chip. Hope that helps some.

 

there is a formula, and I can't remember right off, for measuring the effective gear ratio when you alter the tire circumference. The larger tires would lower your ratio somewhat (numerically speaking) but if you're not planning on making a habit out of towing/hauling 10,000+ loads everywhere, your V-10 is totally awesome and will most definately be up to the task.

Yah, and those meaty tires will look aweful nice too.

 

why can't you just go to the dealer and have the speedo recalibrated for the tire change? It was my understanding that it was completely possible, considering it's all computer controlled, to go into the computer and change this information so your speedo and odo was correct.

Matt

 

Check out these two sites.

The first explains how to correct the odometer.
http://www.4wheelpartsadventures.com/adventures1/htm/default.htm
click on Choosing the right tire

The second tells you how to do the math of determining what your actual odometer is reading for bigger tires.
http://www.4wheelpartsadventures.com/adventures2/htm/default.htm
click on Choosing the right tire part 2

 

What is the biggest tire you can fit without rubbing on a superduty?

 

I'm not sure exactly, but I have seen pictures with 33 x 12.5 on a super duty without any modification. The stock tires are almost the same as 31's. I believe 35's could fit on there with out any fender mod's, but i'm not sure about tire rubbing. If you get new rims with a different offset you might be able to over come the rubbing. I will be looking into doping the same thing when these tires get worn down.

 

The largest tire that I have read someone using on the original rim was LT315-75-16's I've read two different notes from people who have said these were installed by the dealers (swapped for OEM 265-75-16's) on the brand new trucks as a matter of course. Both notes mentioned no problems with clearance. HOWEVER! I have also read folks who have installed LT295-75-16's who said that they needed to add a steering stabilizer (some superduty's have them from the factory)to handle wobble and that clearance was about maxed out with no contact but no room to spare. My F350 came with 265-75's and I'm going with 285-75's when the originals wear out. I think 295's may be pushing it on the OEM 7 inch wide rims and I don't want any wear problems on a set of tires that will cost ~ $650 installed!

 

i just put 305 goodyears on my 2000 250 and they fit excellent with a ton of clearance still left. they are the same asa 33 12.50.....rides great and looks sweet

 

 

I have a V10 with the 4.30's and I went to BFG 295/75-16's on 16X8 Weld Racing Wheels. The 295's are a 33-inch tire and by my calculations, they effectively changed my gear ratio to 4.10. Now 4.10 is still a pretty tall gear so my performance has not suffered at all. In fact, my mileage has actually gone up just a hair.

As for clearance, I get just a touch or rub on the plastic fender skirts on the inside of the wheel wells, but nowhere else. They perform great! I do think my steering would benefit from a stabilizer (I have a bit of right drift) but it's not too bad at all.

As for looks, forget about it. The difference is like night and day. Those 265's might look good on a Ranger or an S-10 but a real truck needs at least a 33-inch tire.

Have fun with your mods.

 

i have the snow plow pkg, which ads approx 1.5 inches of clearance to the front end i have no dral anywhere, nothing but air calling for a 35 inch tire, also mine already has a stabilizer on it from factory.