I see alot of post here on tire up-grades and was wondering what the effects of going with oversized tires have on the truck ? Also what effect would going with a lower profile tire have on the truck? Can you cause any damage to the drive train ?

 

I am at work now... but I am replying here now to remind me check back later with some info

 

Depends on how you + size the tires


Bigger rims + bigger tiressame rims + bigger tiressame size rubber, bigger rims

 

once again, Tylus eliminates the need for anyone else to add...

what he said...

 

I try



also forgot to mention the rolling resistance that wider tires will cause

so not only do you lose braking power, acceleration...but you also lose MPG since the wider tire has more friction/rolling resistance





but in the end, + sizing tires does look awesome on these trucks...can't wait to get some myself

 

With bigger tires, you will not be able to tow as much either. And it does put more stress on your steering componets. So I hear. That doesn't seem to have ever stoped anybody from doing it.

 

i couldnt have said it better myself !!!

 

It's possible that your speedo will be affected, your accelleration may be slowed (like lowering your axle ratio), and it's possible to 'overpower' the stock shocks, affecting the ride. Brian

 

Ok, so how do you 'compensate' for the larger rim/tire combo? Get stiffer springs? Get a heavy duty strut?

Im not so good at suspension so walk me through this one please.

 

I have an 08 XL 150 and I went from the stanard 17 inch wheel to a 18 inch Ford wheel. My dealer is unable to program my truck for the errors in my speedo. I also added cruise and that program took with no problem.

 

The only way I know to correct speedo reading for other than stock tires is to install a custom tune that allows such.

 

Tylus...I disagree a bit on larger wheels, same size rubber...

Larger wheels weigh more, which does do some things to the way it will handle. Increased rotational inertia means less acceleration and braking, as you said for the other configurations, just not as much.

Also, an effect you didn't mention was increased unsprung weight, which is what causes problems with shocks, and a rough ride. If you're looking for a nice ride, lighter is better! Never did find exact specs on how much the factory 20s weigh, but I've heard numerous times that they are significantly heavier than smaller rims....

 

I've actually looked it up before Crazy. Couldn't find the specs for Ford wheels, so I used the postings off of Tire-Rack.Com. Did a 18" to 20" comparison.

Took the weight of several 18" rims and the weight of their rubber
then
Took the wieght of several 20" rims and the weight of their rubber (same diameter as 18" rubber)



in most cases, the weights were within 1-5 lbs of each other going from 18" to 20" tires...usually the big wieght differences were with huge gaudy rims. when we are talking about 85+ lb combos...well that few extra lbs of weight is negligable in my eyes


now if you upgrade to + size rims...and then + size the tires...I 100% agree with you.

 

In my case . I chose to go with the factory steel rims (Winter Months Only) I also went with Cooper M&T 255/60/R17. According to the chart at 60mph I will actually be going 64mph. Stock tire size is 255/70/R17. I am waiting to finish off the oem tires and go with 33's.Yes I have 2.5" leveling kit.
Factory

Winter