If I wanted to put 33" tires on my stock ride hight 90 k5 what wheel offset and width rims would I need if I went with 33 12.5 15 mud terrain tires...
thanks
thanks
CK5
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33" tires on stock 1990k5
- Thread starter Justin Fleming
- Start date
You can run 33s on your stock wheels, no need for new wheels with different offset etc. They may rub when flexing and turned depending on what kind of shape your springs are in but if you don't go off-road you'll be fine. Lots of people run 33s stock.
Do you already have stock wheels?
Not going to be a huge help, but I can tell you with the stock 6 lug steel wheels, 33x10.5R15's will clear in the front under any conditions I've ever put them in.
Probably just too many variables present to say X offset/width will work with the x12.5's.
I did this awhile back. Doesn't seem like much, but again, with differences such as spring height/wear, body mount condition, wheels being used, advertised vs. actual height/width, and day of the week, your results may not be what you want:
You can calculate this (Pythagorean theorem) but square the width and "length" (12.5 squared + 33 squared for a 33x12.5 tire) to get the actual "length". In this case 35.3"
A 10.5" is 34.6"
Long story short, when the wheel is turned (when tires typically rub) the 12.5 tire is .7" "larger" than the 10.5
Not going to be a huge help, but I can tell you with the stock 6 lug steel wheels, 33x10.5R15's will clear in the front under any conditions I've ever put them in.
Probably just too many variables present to say X offset/width will work with the x12.5's.
I did this awhile back. Doesn't seem like much, but again, with differences such as spring height/wear, body mount condition, wheels being used, advertised vs. actual height/width, and day of the week, your results may not be what you want:
You can calculate this (Pythagorean theorem) but square the width and "length" (12.5 squared + 33 squared for a 33x12.5 tire) to get the actual "length". In this case 35.3"
A 10.5" is 34.6"
Long story short, when the wheel is turned (when tires typically rub) the 12.5 tire is .7" "larger" than the 10.5
Moosehunt
Registered Member
OK I have a bone stock '90 k5 and I'm running a set of nearly worn out 33/12.5 pro comps, if I back out of the driveway while turning or enter driveway or parking lot while turning I get a rub, not real bad but enough to cause me concern (I haven't been off-road with these tires since I got them, had about 1/3 tread left when I acquired them in a trade)
I'm needing new tires soon I'd like to stay with 33/12.5's, I like the stance of the Blazer with these tires.
I've always run BFG 32/11.5's before with no issues even flexed hard on steep downhill hard turns.
So my question is would a set of 1" zero rates give me clearance I need? Can't find the rub spot, but suspect the front lip of the fender well.
I would appreciate your thoughts, especially from you guys that have dealt with these issues, Thanks in advance.
Dan
I'm needing new tires soon I'd like to stay with 33/12.5's, I like the stance of the Blazer with these tires.
I've always run BFG 32/11.5's before with no issues even flexed hard on steep downhill hard turns.
So my question is would a set of 1" zero rates give me clearance I need? Can't find the rub spot, but suspect the front lip of the fender well.
I would appreciate your thoughts, especially from you guys that have dealt with these issues, Thanks in advance.
Dan
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You'd have to see where the rubbing occurs, then figure out if the body going up 1" relative to the tire will help.
The centerline of the hub, parallel to the ground, is going to give you the maximum tire diameter. If the body going up 1" increases the fender opening relative to the centerline of the hub, then the only question is, is that enough?
If you are limiting your turns or how hard/fast you hit bumps with the wheel turned to try and avoid rubbing (I would be) then you may be tricking yourself into thinking the rubbing is minimal. Not saying it ISN'T minimal, but with the important dimension deciding clearance and rubbing being only .7" (in most cases), it's a tough call unless clearance increases by a large amount, which is unlikely.
This all seems like a lot of work to make tires fit that don't want to. Either cut the fenders, or run 33x10.5R15's IMO. Already have to get new tires, why not get ones that fit?
Edit: pretty sure in thinking about it, the hub is already below the fender, so tire diameter/width is going to be more difficult to estimate clearance with. And no way to measure statically that is 100% I have found, although getting one rear tire off the ground, flexed decently, then doing the same for the opposite front is supposed to give a pretty good approximation.
The centerline of the hub, parallel to the ground, is going to give you the maximum tire diameter. If the body going up 1" increases the fender opening relative to the centerline of the hub, then the only question is, is that enough?
If you are limiting your turns or how hard/fast you hit bumps with the wheel turned to try and avoid rubbing (I would be) then you may be tricking yourself into thinking the rubbing is minimal. Not saying it ISN'T minimal, but with the important dimension deciding clearance and rubbing being only .7" (in most cases), it's a tough call unless clearance increases by a large amount, which is unlikely.
This all seems like a lot of work to make tires fit that don't want to. Either cut the fenders, or run 33x10.5R15's IMO. Already have to get new tires, why not get ones that fit?
Edit: pretty sure in thinking about it, the hub is already below the fender, so tire diameter/width is going to be more difficult to estimate clearance with. And no way to measure statically that is 100% I have found, although getting one rear tire off the ground, flexed decently, then doing the same for the opposite front is supposed to give a pretty good approximation.
Try a zero rate first.
Martin
Martin
Zero rates are a better choice then a body lift in my book.
I like a 1" body lift. Anymore looks silly to me.
Martin
Martin
Moosehunt
Registered Member
You're a mind reader, ("If you are limiting your turns or how hard/fast you hit bumps with the wheel turned to try and avoid rubbing (I would be) then you may be tricking yourself into thinking the rubbing is minimal.")
Exactly what I've been doing.
Like you said I need to find exactly where the rub is and procede. (Note to self -also the 'New' 33's will be a little larger in diameter than these worn out one's I'm running now)
If it's the front of the fender opening as I suspect, do you think those guys that do "Fender Rolling" could reshape the fender opening enough? I'm Not exactly clear on the Fender Rolling process and what can be accomplished.
Just thinking out loud.
Where I hunt it's Sandy, real Sandy the more the trails get beat up the fluffier the sand gets and the added floatation , fat foot print of the 12.5's would be welcome. I end up airing down to 18 psi now.
I'm just weighing my options and trying to figure a way to run the 33/12.5s without tearing up them or my Blazer.
Hell it isn't life or death I can always go back to 32/11.5's and know I have no clearance issues.
Thanks for the input!
