I have three questions for y'all.

1st: this might be a question for NumberDummy but if any of y'all can answer then that's ok........a 1979 F100 4x2.....what size were the tires when it came from the factory?

2nd: did all 2wds come with the same tires, and all 4wds come with the same tires?

3rd: when a person posts in their gallery that they have for example 39.5 tires, does that mean that they have 39s or 40s? do you round up on those things or not?

 

1. 79 F100 2wd used F78-15, G78-15, GR78-15, H78-15, L78-15, LR78-15, or you could get a tube tire 7.00-15, take your pick.

2. 79 F-150 4wd used L78-15, LR78-15 or a 10-15, they also had a 7.00-15 tube tire as well.

3. No, some manufacturers make a 39 1/2" tall tire, if you actually measured it tho it would probably be close to 38 1/2-39" tall. Most all tires run within an inch of what they claim, very few are actual height size.

 

I usedto have the conversion chart for the old letter tires to compare size to the metric but can't seem to locate it now. Anyone know what metric would be equal to the F78-15 and te L78-15?

 

so, ranger429 you don't know what these letters/numbers mean in regular form? for example 225/75/15. as tankrsc said is there a way to convert these numbers?

and since the tires don't measure up to what they are classified as could that be because someone didn't put enough air in them?

 

Coker Tire Resource - Bias Ply to Radial Conversion Chart

Air will change the overall height of the tire but it has nothing to do with what I mentioned. The actual tire height the manufacturer claims versus the actual tire height don't always match.

 

on back according to the chart I have L78-15 (255/70/15). and on the front I have H78-15 (225/75/15). thanks for the charts. oh and btw I don't have the original tires on my truck in case yu were wondering.

 

My 39.5 swampers measure 38 3/4" when measure from the pavement. The tire height will also vary depending on rim width.

 

Same with my bf goodrich radial t'as , a 275/60/15 are suppose to be 28" tall and they measure 27 on a 8 inch rim . I was trying to figure rear tire height stock specs for gearing and speedo accuracy , stock tire rear height ? May go to a taller tire next time for better gas mileage and lower rpms .

 

If you are curious the blue truck in my Gallery had 255/70-15 when I got it. That is when I took all the pics the wheels are 15X7. When I get another set of tires for the truck I will run those on back again. The front ones in thepic are 235/75-15's I will go with a 225/70-15 up there whith the new ones. Just thought you might want to see what they look like befor you guy. The 255/70's are about and inch taller than the 275/60's on the same rim.

 

ken selvy heres a link to figure out how tall your tires are (without a tape measure)

Novak Conversions - Gearing & Gearing Math for Jeeps

 

Anyone have any info on the old q78's that everyone used to run?? Super tall and skinny. Been looking for a replacement along those lines..

 

The only thing I have seen in that size in years is a Super Swamper