Ford F834 Posted August 8, 2018 Share Posted August 8, 2018 I appreciate all the posts gentlemen. Good points to consider as I start shopping. Gary: yep. I'm tracking all of the options on a spreadsheet, out of necessity. Somewhere after the 2nd kid, I wasn't able to keep more than 3 items in my head without writing them down. I welcome more experience and advice if anyone has some to offer. Hi, sorry I am late to the party... I did get wrapped up in the math of gearing for my build, and I made pages and pages of calculations for different transmissions, axle gears and tire sizes in my quest for the perfect combination. There are some good online calculators if you don’t like to do the math yourself. Here is one: http://www.wallaceracing.com/calc-gear-tire-rpm-mph.php I am really enjoying the tires that I bought. The 235/85/R16 help the engine revs with the non-overdrive transmission. They are heavier, I guess, than stock rims and tires, but not drastically different. It is what I have always run on my heavier F250/F350’s. I wanted the load capacity and also ply rating for overlanding. I had to buy aftermarket rims which was sad since I have a really beautiful set of silver spoke wheels that I got from David, but it was the right choice. I am not a fan of wide tires. They are good for mud and soft sand I guess, but I went for the tall skinny for good mpg and snow traction. Link to comment Share on other sites More sharing options...
1986F150Six Posted August 8, 2018 Share Posted August 8, 2018 I had to buy aftermarket rims which was sad since I have a really beautiful set of silver spoke wheels that I got from David, but it was the right choice. I am not a fan of wide tires. They are good for mud and soft sand I guess, but I went for the tall skinny for good mpg and snow traction. Bring the set of wheels to 2018 Garagemahal Ford Truck Show for the swap meet [selling of good used parts]! Link to comment Share on other sites More sharing options...
Ford F834 Posted August 8, 2018 Share Posted August 8, 2018 I had to buy aftermarket rims which was sad since I have a really beautiful set of silver spoke wheels that I got from David, but it was the right choice. I am not a fan of wide tires. They are good for mud and soft sand I guess, but I went for the tall skinny for good mpg and snow traction. Bring the set of wheels to 2018 Garagemahal Ford Truck Show for the swap meet [selling of good used parts]! Good idea David! I should have room for more parts this year! Link to comment Share on other sites More sharing options...
Dyn Blin Posted August 8, 2018 Author Share Posted August 8, 2018 I’m taking the truck on an 1800 mile trip to visit family in Lolo, MT in October... Slightly off topic, but my wife and I did a coast to coast motorcycle trip back in 2011. We traveled west all the way across Canada, and then east all the way across the northern USA. We stayed in Lewiston Idaho, and then took hwy #12 east from there and then over the Lolo Pass into Montana. I've often told people, that the drive east from Lewiston and into Montana has to be one of the nicest drives in the country. The way the road meanders along following the river is really very pretty. Anyway, sorry to veer away from tires here...but when you mentioned Lolo MT, you reminded me of a very beautiful part of the country, and somewhere I'd love to have had more time to explore. Small world. I grew up in Moscow, ID (30 miles north of Lewiston on the "Spiral Highway"). My brother and his family have since moved to Lolo. I take a motorcycle joyride at least once a year in a long loop from NorCal to see family in Moscow and Pullman, then spend time with my brother and his family in Lolo. When all the kids are out of school, the wife and I will head up to join them. It really is beautiful country, and some great history, too. It's funny, I spent my teen years and college working to get away, and now I count the years until I can get back. If you ever head up there again, reach out to me and I'll give my .02 of routes and stops. Link to comment Share on other sites More sharing options...
Dyn Blin Posted August 8, 2018 Author Share Posted August 8, 2018 Hi, sorry I am late to the party... I did get wrapped up in the math of gearing for my build, and I made pages and pages of calculations for different transmissions, axle gears and tire sizes in my quest for the perfect combination. There are some good online calculators if you don’t like to do the math yourself. Here is one: http://www.wallaceracing.com/calc-gear-tire-rpm-mph.php I am really enjoying the tires that I bought. The 235/85/R16 help the engine revs with the non-overdrive transmission. They are heavier, I guess, than stock rims and tires, but not drastically different. It is what I have always run on my heavier F250/F350’s. I wanted the load capacity and also ply rating for overlanding. I had to buy aftermarket rims which was sad since I have a really beautiful set of silver spoke wheels that I got from David, but it was the right choice. I am not a fan of wide tires. They are good for mud and soft sand I guess, but I went for the tall skinny for good mpg and snow traction. Thanks for that. I'm looking to stay "skinny" too for the occasional romp up to Tahoe in the winter, and keep the road friction and rub to minimums. Now I'm thinking about the possibilities with 16" wheels, but the outlay for new rims and tires will be too dear to budget for prior to the trip, unless I find something good at the yard. For 15", it looks there there are a few choices at 31 or 33 and 10.5 that aren't so soft I'll be looking to buy in again in too short a time. Link to comment Share on other sites More sharing options...
Ford F834 Posted August 8, 2018 Share Posted August 8, 2018 Thanks for that. I'm looking to stay "skinny" too for the occasional romp up to Tahoe in the winter, and keep the road friction and rub to minimums. Now I'm thinking about the possibilities with 16" wheels, but the outlay for new rims and tires will be too dear to budget for prior to the trip, unless I find something good at the yard. For 15", it looks there there are a few choices at 31 or 33 and 10.5 that aren't so soft I'll be looking to buy in again in too short a time. Just FYI, the 31x10.5’s are ~not 31” tall. They are more like 30” new, 29” when worn down... and wider than I like. I don’t know how they get away with calling them “31’s” but they might be a bit disappointing for rpm’s if you are expecting a true 31” diameter. Link to comment Share on other sites More sharing options...
Dyn Blin Posted August 8, 2018 Author Share Posted August 8, 2018 Just FYI, the 31x10.5’s are ~not 31” tall. They are more like 30” new, 29” when worn down... and wider than I like. I don’t know how they get away with calling them “31’s” but they might be a bit disappointing for rpm’s if you are expecting a true 31” diameter. Boy, you're not kidding, that would be a disappointment after plugging all these numbers in and finding out the RPM savings isn't what I expected. Thanks for the pointer. Link to comment Share on other sites More sharing options...
Gary Lewis Posted August 9, 2018 Share Posted August 9, 2018 Boy, you're not kidding, that would be a disappointment after plugging all these numbers in and finding out the RPM savings isn't what I expected. Thanks for the pointer. Tire Rack gives you the rolling diameter on all of the many tires they sell. And you can compare several of the same tire sizes in order to determine which one to buy. Link to comment Share on other sites More sharing options...
Dyn Blin Posted August 9, 2018 Author Share Posted August 9, 2018 Tire Rack gives you the rolling diameter on all of the many tires they sell. And you can compare several of the same tire sizes in order to determine which one to buy. Perfect Gary, & thanks for the additional resource. (...adds column to the spreadsheet) Link to comment Share on other sites More sharing options...
Dyn Blin Posted November 9, 2018 Author Share Posted November 9, 2018 Perfect Gary, & thanks for the additional resource. (...adds column to the spreadsheet) I figured I'd come back to close the circle on the topic: I got lucky and picked up a set of brand new "take-offs" from a local shop with less than 100 miles on them: 31x10.5x15 mud and snow tires with a mild tread. On the long trip, it was hard to gauge their affect on mileage given the load in the bed and the winter formulation of gasoline that hits CA and NV in Oct & Nov, but the immediate noise & vibration improvement in the ~300 RPM reduction was a pleasure, especially at the 55-70MPH range. Although the speed limit hits 85 on some parts of the long loop up to the panhandle and western MT, I'm usually in the left lane with the big rigs at an easier pace. Since I got home, although I really don't notice much change in clutch feel getting it rolling unloaded. City mileage has stayed the same- I expected a bit of drop with the increase in contact patch and resistance. Highway has seen roughly a 10% improvement in mean MPG, and I hope to see a bit more all things equal when spring sees the return of the better gas. The only other variable I can account for is an oil change back to 10w30 (Rotella T5) from full-dino 10w40. However, given the mild CA weather this fall, I'm not sure that can account for any appreciable difference in the improvement percentage. Overall, a worthwhile improvement over the 28" tires for me. Link to comment Share on other sites More sharing options...
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