I'm on hold with my injectors until I get a little more info from vendors. Meanwhile... my tires have as much tread as I have hair. The coated stock wheels have calcium chloride tunneling under the coating and dining on aluminum. The round parts under the truck are as distracting as a muumuu on a body builder.

I'm going to keep the rims understated like the originals, but I'm looking hard at the diameters. I heard a rumor that 17" rims are more common for tire sizes and I'm not finding that to be the case. I can find plenty of 16s and 18s, but the 17s really narrow me down to the fugly tires. I recently read a topic on 19.5" rims and tires and I didn't like what I found there. I don't want 20s because it augments the harsh ride of this era of Superduty - I can just see me hangin' on to the wheel with those.

So... it looks like 18s are the call for my goals (I still have to find them with the load rating). Now the tires. LT is a given... a sleepy-head tire guy once put P tires on my tow vehicle (E350 van) and that thing was swayin' like a drunken camp counselor singing "Kumbayah".

The first number (tread width) is 265 now... it just looks a little wide to me, but I'm thinking in terms of winter roads. Narrower tires usually fare a little better. Knocking the width down to 245 is about 3/4" norrower, but the load rating typically plummets at that width. 255 width is about as common as Duramax fans here, so I might be stuck with 265s.

With the tire width all but dictated to me, and rim size being a fixed number, this leaves the tire height - which directly effects diameter. I like the mileage I'm getting and I have have stock suspension - with zero desire to lift anything. If I go with a height ratio of 70, that gives me a 1" bump in diameter.

I found tires with the size LT265 70R18 with a load rating of 124 (one notch up from a stock 123) and a speed rating of S (two notches up from a stock Q - 99 MPH). I have AE to program in the new diameter so the speedo/odo are correct, and it looks like I have plenty of clearance in the tire well for this small bump in size.

Here's are the questions I have left: Has anybody else here done this? How did it work out?
Here's an invitation: Go ahead and blast away at anything that smacks of disinformation here, I can't be an expert on all things tire-related just by surfing.

 

Tugly: My thoughts re tires are discussed under the screen name "E350" primarily on pages 4 and 5 here:

Sportsmobileforum.com • View topic - Best tire choice??

As you know, vans come or at least used to come with 16" rims. So, when fitting the larger rotors during a 4x4 conversion, the accepted upgrade is to go from 16" to 17" rims with spacers on the rear axle to fit the F350 bolt pattern (until recently, the van wheels had a different bolt pattern !!???).

[BTW, the best way to change the rear diff. bolt pattern is to replace the narrower E350 semi floating axle with a full floating axle from a F350. This also provides the necessary speedo output for the E350 4R100 which permits the use of the NV271 instead of the weaker BW1356.]

Tires for 17" rims are indeed harder to find. So, the available tires, tread designs (and even a small war on studs) are discussed in the above link.

For a different take on things, you may want to change your E350 to the F350 bolt pattern. And have the option of a second set of wheels and tires and be able to switch between vehicles (i.e., studs).

I read that you have driven on all 60 types of snow that the Eskimos have words for, so for fun you could even enter the stud flame war on the Sportsmobile forum!

 

I run 17's... My wife runs 18's...

Doubt there is anything wrong with your wheels however. Get them powdercoated and keep on trucking...

Mine with 17's before and after powder coating (because of the CC ruining the finish...)





Chelseas X with 18's before and after powder coating (same reason)

 

If you tow Tugly, then E rated are, well i would want. If driving in snow (if you do), then do you airdown at all? E rated probably wouldnt give you a bigger footprint to help bite. Maybe a D would be better than. Going to an 18 wheel, you got more mass for brakes to stop. I know when they went to the bigger wheels for later years, they stepped up the size of brakes/calipers. Something to consider too.

I went from 285/75 to 265/75, didnt care that my footprint narrowed some, but they look good under truck, fill the wheel cleanly and the price, i couldnt pass up.

 

I'd better calrify something here. I had and E350 with a 460 years ago, and the regulars here are already familiar with my current tow vehicle - Stinky, the wonder truck.

The powder coating idea is simple and inexpensive... I really like it. I have easy access to powder coating here, major mulling will ensue.

I never considered bigger brakes with the bigger rims. That's an option, right?

I like the look of the 18" rims on the Ex... they look more proportional than my dink 16s.

My current tire size is LT265 75R16 with crusty plastic-coated aluminum wheels and it just looks wrong on so many levels.