Tires & RPM's

#1
I need to buy new tires soon for my F-250 gasser and was curious if anyone knew how much the rpm's would change if I went to a bigger tire. I currently run 235/75R16 and am thinking of going to a 285 or 295/75R16. I have asked different tire dealers and they cant give me a straight answer. I don't know if there is an answer out there or not but i just don't want to find out the hard way.
Thanks for any info,
Mike
 
#2
Re: Tires & RPM's

You will probably invalidate the warranty on your F250 if you use a different tire from those specified in the owner's manual. It changes more than the rpm's. Just a thought. If you don't care about the warranty, then go with it. I've done that with a pickup truck briefly and it worked fine.
 
#4
RE: Tires & RPM's



I need to buy new tires soon for my F-250 gasser and was curious if anyone knew how much the rpm's would change if I went to a bigger tire. I currently run 235/75R16 and am thinking of going to a 285 or 295/75R16. I have asked different tire dealers and they cant give me a straight answer. I don't know if there is an answer out there or not but i just don't want to find out the hard way.
Thanks for any info,
Mike



Mike, I am pretty sure, when you change from a section width of 235 mm to 285 mm that is 50mm (about 2 in). You have to be very careful that on the duals that the tires don't rub each other. You may have to have different rim setup also. I would be very careful about that big of a change. I would expect the diameter (etc, rev/mile) would also have to be checked. As stated by others, you could be way off on your odo reading after such a change, and it may affect the hp/torque curve of where your rig operates as referenced to engine/tranny/drive-train.



good luck !!
 
#5
RE: Tires & RPM's

Thanks for all your replies. I have sent an email to Ford & Goodyear asking for their opinion/fact but for the time being it looks like I will stay with stock size.
 
Top