tire size question

[big_hoovie]

I was wondering if there is a chart or calculator for figuring out the size of the tires I'm running. I'm running 235/75/15s and I'd like to know the height in inches of the tires I've got(I'm between tape measures at the moment)

 

[Vanquish502]

28.88 Inches.

 

[hiridin]

i believe thats somewhere around a 29" tire.

 

[big_hoovie]

ok, thanks. Is there some chart I can consult that might have these figures, or are these estimates?

I'm just trying to determine how much lift I will get by switching to a 31" tire size, which if these are 29"s won't be a whole lot(but a lift is a lift).

If I change to 31" tires, should I regear(I'm running 3.55 gears now), or would my current ratio be sufficient?

 

[spdy0001]

235/75/15

235 = width in MM
75 = sidwall height / % of width
15 = wheel size

75% of 235 = 176.25mm
176.25 mm X 2 = 352.5mm(total sidewall height)
352.5mm = 13.88"
13.88" + 15" = 28.88" total tire height

You can use this calcualation to figure any tire's height. Also there is a sticky floating around that gives a rought estimate of what size tire you should be able to fit with diffrent size lifts.

Also remember that if you go to a 31" tire thats a little over 2" bigger, but will only lift the vehicle 1".

A gear change to 3.73 would put you right back to stock ratio, but you might be ok with your stock gear depending on what you are using the truck for.

 

[big_hoovie]

It's primarily my daily driver(city driving, mainly), but I would like a little extra clearance for when I do take it off road(I do realize that with larger tires comes worse milage). I doubt that I would use it for towing more than once in perhaps two years(for moving, but not likely in the immediate future).

 

[hiridin]

3.55's and 31's will suck big time :thumbdwn: no power unless yer in 4low. trust me i know... and if yer even considering towing u need 4.10's with 31's.

 

[FROADER]

Here is an actual converter for you.

http://www.s-series.org/htm/calc/tiresizeconv.htm

 

[big_hoovie]

thanks for all the responses, it's a lot of help.

 

[Jason94sport]

3.55 will run 31 ok. They will sap some power, but it's not anywhere near the range with 3.27 gears like my X has.

 

[LBarr2002]

A gear change to 3.73 would put you right back to stock ratio, but you might be ok with your stock gear depending on what you are using the truck for.

There is no reason you should ever regear from a 3.55 to a 3.73. You should be fine with 3.55, but if you did want to regear that change would definitely not be worth the price.

 

[hiridin]

yeah but 3.55's and 31's will be like stock tires (29") and 3.27's. which sucks even with stock tires... the highest gears that ever should've been put in these trucks is 3.73's with 4.10's being the standard gear. my truck was useless offroad with 31's and 3.55's... i couldn't do anything without being in 4low. hell i couldn't so much as drive over a curb in high gear without burnin the hell out of my clutch jus to barely get over it. i'm sure its a little better with an automatic tranny but they can barely handle themselves stock let alone when u put stress on it.

 

[spdy0001]

There is no reason you should ever regear from a 3.55 to a 3.73. You should be fine with 3.55, but if you did want to regear that change would definitely not be worth the price.

I was just stating that 3.73 gears would put him back to stock ratio, not that I recomend making that small of a change. However if this is going to see the highway 98% of the time that gearing is probably fine and you could get a 3.73 axel out of a junk yard

 

[big_hoovie]

I'm not sure what you mean by 'stock ratio'...3.55 was offered as a stock option..so was 3.27 and 4.10. Unless you are referring to what was offered standard, as versus options dealers offered.

If I were to regear(or find a set of axles from a salvage yard) I like to think I would go for the 4.10s as going from 3.55 to 3.73 isn't much of a jump.

I suppose, to offset any power loss from going to slightly larger tires, I could do some performance mods, but I'm not sure what inexpensive options I've got(they kind of HAVE to be inexpensive, as I may have to have the tranny rebuilt in the next few months)

 

[TheFox88]

I'm not sure what you mean by 'stock ratio'...3.55 was offered as a stock option..so was 3.27 and 4.10. Unless you are referring to what was offered standard, as versus options dealers offered.

If I were to regear(or find a set of axles from a salvage yard) I like to think I would go for the 4.10s as going from 3.55 to 3.73 isn't much of a jump.

I suppose, to offset any power loss from going to slightly larger tires, I could do some performance mods, but I'm not sure what inexpensive options I've got(they kind of HAVE to be inexpensive, as I may have to have the tranny rebuilt in the next few months)

As far as i know there was never any 4.10's stock, at least in a first gen.

 

[LBarr2002]

As far as i know there was never any 4.10's stock, at least in a first gen.

I've heard that there were a few. I've never seen one, but the axle code sheet I have lists a 4.10 open and a LS.

 

[bmxking5]

I've heard that there were a few. I've never seen one, but the axle code sheet I have lists a 4.10 open and a LS.

They were only available from 95+

 

[LBarr2002]

Oh, learn something new every day. So I guess you could pull a 95+ 8.8 from a junkyard w/ 4.10's and get disk brakes in the process....

 

[bmxking5]

Exactly. If you find two of them, you can get one for yourself, and sell the other to Jeepers for mucho money. Those things are like gold to them.

 

[big_hoovie]

so what axle code(s) should I look for, and does it matter what year I pull them from? Also, does it list on the door sticker if the axle has limited slip, or would that be in the axle code(bring a list w/me when I go) and I assume that I would have to pull both the front and rear axles to match the gearing, right?

Since I did my brakes, I have been wanting to switch to rear discs(of course that was last weekend), so that would definitly be bonus , and I would happen to have a set of axles that jeepers may be interested in(dunno what kind of demand there is for 3.55 gear ratio)


LBarr: Question about your X's - did either one of them come with the center console bewteen the two front seats, or do you have that stupid fold away arm rest on the drivers seat?