Newb with 99 Yukon 4x4 with tire size question on stock suspension

[WalterMitty]

I'll add 2¢ here not because I consider myself an expert but because I learned something the hard way that in hindsight probably should have been common sense; but I missed it.

The torsion bars do not control the limits of suspension travel. You can adjust them to raise or lower the relative position of the front end, but the parts that actually stop wheel travel are unaffected.

I put 285's on my 1996 and had no rubbing issues under normal driving conditions. When I finally got the truck into a situation that pinned the right front "A" arm against the stop, I had a problem. Unknown to me (I should have checked) the stock bump stop was blown out and did not stop wheel travel where it should have. So I put the tire into the wheel well, cut the tire and tweaked the metal.

If you have a rubbing issue that you "solve" by adjusting torsion bars, be prepared to have it return with a vengeance on that day you put the suspension at the limit. In my experience that situation may not permit you to do anything but drag on through hoping the tire doesn't puncture or turn the fender lip inside out.

I apologize in advance if this is painfully obvious and I'm just a moron for not knowing it, but it took me several days to do a post mortem and find the root cause of the problem.

.

 

[sparg93]

Highlander - unless you plan on really lifting that rig, I don't think the 15x10 are going to look right. Rigs that I have seen 15x10's on typically have suspension lifts (4"+) and big tires....I'm not sure how 31's would look.

As Bowtie mentioned a 4" backspace is REALLY going to stick out far...and if you're not lifted, it's going to be really obvious.

I hate to say it, but if you're not going to give that truck a full suspension lift, I don't think the 15x10's are the right rim for you. I'm still a newb with suspensions, so don't ever confuse me as an expert

Also, a few months back when I was also trying to figure out what would fit my truck, I posted a page specific to our trucks that included a variety of tire/rim sizes and what was needed to make them fit. If I remember correctly, look for the post in the Lifted section, it may provide you with some useful intel.

 

[highlander]

I wasnt going to do the full shackle flip. There are some shorter aftermarket shackles on Ebay that give you 1.5 to 2.0" lift over the factory longer ones. Just wondering if anyone has ever used these on the rear?

I dont mind the tires sticking out past my fenders, I am more concerned with the clearance while turning the wheels.

The tire I am looking at running on the 15 x 10 wheels are 31 x 10.50's now.
That would put my tire tread/sidewall basically flush with the wheel width.
Sidewall height will be about right at 7.5".
I guess the best thing I can do is pull off one of my front wheels and put the 15 x 10 rim on the Yuke and turn it back and forth to its full radius and take measurements out 7.5" at several different points to see how much clearance I have......does this sound like a good way to check clearances?

---------- Post added at 04:03 PM ---------- Previous post was at 03:59 PM ----------

Hey this is good info. I have already noticed that at least one of my front rubber bump stops is completely gone. Guess first thing is to make sure I get all the rubber snubbers and stuff checked out and replaced if needed first.

I'll add 2¢ here not because I consider myself an expert but because I learned something the hard way that in hindsight probably should have been common sense; but I missed it.

The torsion bars do not control the limits of suspension travel. You can adjust them to raise or lower the relative position of the front end, but the parts that actually stop wheel travel are unaffected.

I put 285's on my 1996 and had no rubbing issues under normal driving conditions. When I finally got the truck into a situation that pinned the right front "A" arm against the stop, I had a problem. Unknown to me (I should have checked) the stock bump stop was blown out and did not stop wheel travel where it should have. So I put the tire into the wheel well, cut the tire and tweaked the metal.

If you have a rubbing issue that you "solve" by adjusting torsion bars, be prepared to have it return with a vengeance on that day you put the suspension at the limit. In my experience that situation may not permit you to do anything but drag on through hoping the tire doesn't puncture or turn the fender lip inside out.

I apologize in advance if this is painfully obvious and I'm just a moron for not knowing it, but it took me several days to do a post mortem and find the root cause of the problem.

.

---------- Post added at 04:08 PM ---------- Previous post was at 04:03 PM ----------

10-4, I will go to that section of the forum and try to look up your posting and read over it.

My best bet may be to just stick with the factory 16" rims on the Yuke and look at maybe trying to run the 285/75/16" tire size. I just really dont like the way the rims sit way inside the fender wells. I can find plenty of factory oem wheels on Craigslist for the Yuke but they all look to have just about the same rim offsets.

Highlander - unless you plan on really lifting that rig, I don't think the 15x10 are going to look right. Rigs that I have seen 15x10's on typically have suspension lifts (4"+) and big tires....I'm not sure how 31's would look.

As Bowtie mentioned a 4" backspace is REALLY going to stick out far...and if you're not lifted, it's going to be really obvious.

I hate to say it, but if you're not going to give that truck a full suspension lift, I don't think the 15x10's are the right rim for you. I'm still a newb with suspensions, so don't ever confuse me as an expert

Also, a few months back when I was also trying to figure out what would fit my truck, I posted a page specific to our trucks that included a variety of tire/rim sizes and what was needed to make them fit. If I remember correctly, look for the post in the Lifted section, it may provide you with some useful intel.

 

[sparg93]

Most aftermarket rims for our rigs are going to stick out from a little to a lot...so if you like that look, you're in Luck!!!

Most of the rims I found were 4.5" - 5.5" BS when I was shopping, many more being closer to 4.5" then 5.5". Off the top of my head I can't remember OEM BS, but I would guess it's closer to 6".

I'm not sure if this helps, but here is a side by side of a 265 vs 285.



265's on front, 285's on back (took photo during install, never drove it like this )

 

[highlander]

Took a measurement off my stock rim and its got about a 5.75" backspacing.

Took a measurement off my aftermarket 15" x 10" wheel and its got a 3.75" backspacing. I am going to get a set of 31 x 10.50's mounted onto the 15" rims and give them a try. I know they will stick out from under the fenders but thats OK with me. I am hoping that by staying with the 31" diameter I can still have enough clearance on everything to run them.
If not, then I can always try to crank the torsion bars and put in some shorter rear spring shackles to give me a little more lift.

Someone earlier had mentioned that a 15" rim might have issues with the brake calipers rubbing? I had this issue once on a Jeep CJ with 1 ton chevy axles, but the calipers were larger due to it being a 8 lug axle. I just ground them down a little and they worked OK.

Mine is the GMC 1500 Yukon. Guess my question is has anyone tried to run a 15" rim on theirs and had rub issues with the brake calipers?

---------- Post added at 02:00 PM ---------- Previous post was at 12:21 PM ----------

Please elaborate on the minor modifications required to run the 15" aftermarket rims????

With some minor modification yes.

 

[highlander]

Thought I would update this thread in case anyone else is following it.
I am now running 31 x 10.50 All terrains on the 99 Yukon SLT 4x4. Rims are 15 x 10's with 3.75 backspace.
No problems whatsover. Plenty of clearance, no problems with the 15" rims and no modifications necessary. I do have about 3" of tread sitting outside my fender line, but that doesnt bother me at all.
I am thinking now that I should have went with a 33" tall tire. The 31's do still look a little small on my rig even with just stock height.

 

[sparg93]

Thought I would update this thread in case anyone else is following it.
I am now running 31 x 10.50 All terrains on the 99 Yukon SLT 4x4. Rims are 15 x 10's with 3.75 backspace.
No problems whatsover. Plenty of clearance, no problems with the 15" rims and no modifications necessary. I do have about 3" of tread sitting outside my fender line, but that doesnt bother me at all.
I am thinking now that I should have went with a 33" tall tire. The 31's do still look a little small on my rig even with just stock height.

That's great, glad they fit!! If you had 33's on there, do you think they would rub??

Also, do you have any photos you can post?? I haven't seen many rigs running the setup (i.e. 31's on 15x10's) you are and would interested to see how they look.

 

[highlander]

I will get some pics up hopefully tomorrow. Been dark when I leave out in the mornings to go to work and when I end up dragging in home in the evenings after I leave work.
I had to park the Yuke right after I got the new wheels and tires on it though, cause while changing them out I discovered that the passenger side upper ball joint has about 3" of in and out slop on the tire when its jacked up with no pressure on it. Going to change out both upper ball joints this Saturday and get it back on the road again....