Spare tire and bumper question

I have 33" tires. I extended the factory tire carrier out about 2", lifted the 3rd brake light, cut off the studs, replaced studs with longer bolts. I used grade 8 hardware.
 
Now that I see your wheel, the wheel is the problem. Those are 15x7 wheels off of a 2000 cherokee sport. Most wrangler wheels are 15x8. Depending on how that one inch of wheel width loss affects the offset/back spacing (I'm no good with those terms lol), a simple 1" 4.5 bolt on spacer might fix this problem.
 
Now that I see your wheel, the wheel is the problem. Those are 15x7 wheels off of a 2000 cherokee sport. Most wrangler wheels are 15x8. Depending on how that one inch of wheel width loss affects the offset/back spacing (I'm no good with those terms lol), a simple 1" 4.5 bolt on spacer might fix this problem.

Jeepaholic; this thread is almost a year old so I hope you are still out there. I don't pretend to understand the math you describe. If the wheels I have are 7" and the original Wrangler wheels would be 8", it seems to me that I should have an extra 1" anyway. So, I got lost in there somewhere. The tires are Yokohama 31 x 10.5 R15 LT. The "rack" does not appear to be sagging at all.

I brought the problem up again on a new post in the forums. Chris suggested I start a new thread on subject. I think a new thread would just be redundant. Hopefully Chris will see this post and keep me pointed in the right direction.

Chief
 
was looking at you old pics..is the drivers side of your tire carrier bent?
dscn0662-jpg.webp
 
The problem might be with the wheel back spacing. If it is deeper than the usual TJ wheels, that would move it closer to the tailgate. Add a wider tire, and closing the tailgate might not be possible, without trimming the bottom snubber. If you can mount the wheel with the new tire on the tailgate, but cannot close it, the bottom snubber is the issue. Can you measure the distance left for the tailgate to close once it makes contact with the bottom snubber? Rudimentary drawing of the back spacing shown below, which shows the distance between a straight edge on the back of the wheel and the mounting surface. This is looking at the wheel from the top or side...
upload_2018-2-17_15-51-52.webp
 
I do not believe it is bent. Is there something on the pic that looks bent?
aahhhhh.......I finally see what you are talking about. I will take the tire off tomorrow and check it out. Although I would think that anything that would/could dent the carrier like that would also put a dent in the tailgate. But now I just have to have a look.

Also, another poster asked how big the gap is when the tire is inflated and the tailgate can't be closed. I utterly failed in that description attempt, but I hope you get the drift. I will inflate the tire tomorrow and measure the open gap.
 
I have the exact same problem with my 31's. TR265x75x16" Nittos over a factory bumper. I keep a used tire of the same size tire back there and it just barely clears the bumper but a new tire's larger diameter will not fit- not even close. I am a bit uncomfortable with running a tire that is a bit smaller diameter but it would get me off the trail if I blew a sidewall on one of the new tires — If a front I might put the spare on the limited slip rear rather than on the front that has an Aussie locker. The spare is still a legal tread but stands 1/2" shorter than the new tires.

Please note there is an inexpensive (if I remember right about $35) that replaces your current mount and raises the tire about 2". If I remember correctly you will lose your 3rd brake light unless you do some mods to it. Seems like the seller is either Quadratec or Extreme Terrain.

Here is one choice I found in a quick search that is more like $65: https://www.extremeterrain.com/smittybilt-tire-relocation-bracket-35in-8717.html
 
I have the exact same problem with my 31's. TR265x75x16" Nittos over a factory bumper. I keep a used tire of the same size tire back there and it just barely clears the bumper but a new tire's larger diameter will not fit- not even close. I am a bit uncomfortable with running a tire that is a bit smaller diameter but it would get me off the trail if I blew a sidewall on one of the new tires — If a front I might put the spare on the limited slip rear rather than on the front that has an Aussie locker. The spare is still a legal tread but stands 1/2" shorter than the new tires.

Please note there is an inexpensive (if I remember right about $35) that replaces your current mount and raises the tire about 2". If I remember correctly you will lose your 3rd brake light unless you do some mods to it. Seems like the seller is either Quadratec or Extreme Terrain.

Here is one choice I found in a quick search that is more like $65: https://www.extremeterrain.com/smittybilt-tire-relocation-bracket-35in-8717.html

Phil, the problem is not height.....the problem is, when the spare is inflated, the inside of the tire hits the bumper and prevents the tailgate from closing.
 
Did a little research, the Ecco wheels have 5.5" of backspacing. I was wondering why those would not work the same as my Moab wheels, but it turns out the Moabs have 5" of backspacing,putting them 1/2" further out. That's why it only took a washer or two on the bottom stud of the tire carrier to fix the 'tailgate won't close" issue I had with 31" tires.

Again, how much room you need to close the tailgate with the tire inflated will determine how much to trim off the bottom snubber, if that's the solution. It still does not clear up the mystery of why this hasn't worked for you, as I had similar Jeep wheels with the same backspacing on prior TJs, and 31" tires did not do what you are describing. Maybe the tire mount really is tweaked.
 
Jeepaholic; this thread is almost a year old so I hope you are still out there. I don't pretend to understand the math you describe. If the wheels I have are 7" and the original Wrangler wheels would be 8", it seems to me that I should have an extra 1" anyway. So, I got lost in there somewhere. The tires are Yokohama 31 x 10.5 R15 LT. The "rack" does not appear to be sagging at all.

I brought the problem up again on a new post in the forums. Chris suggested I start a new thread on subject. I think a new thread would just be redundant. Hopefully Chris will see this post and keep me pointed in the right direction.

Chief
I'm still on here, I think a spacer, or trimming the rubber bumps to make them thinner, will help your problem
 
I agree that it sounds like a back spacing issue. Just need to find out what the difference in back spacing. If 1/2" trim all 3 snubbers down 1/2". If it's 1", buy a 1" wheel spacer and be done.
 
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After reading the entire post a couple times, nobody asked what, if any, gap is between the upper bumpers and the tire.
Also, if it is just the lower bumper, I would put washers under the lower spare mount instead of grinding or “shaving” the rubber snubber.
 
After reading the entire post a couple times, nobody asked what, if any, gap is between the upper bumpers and the tire.
Also, if it is just the lower bumper, I would put washers under the lower spare mount instead of grinding or “shaving” the rubber snubber.
He was concerned about not enough threads on the bolts for the lug nuts.....the reason for "shaving" the 1/2" off the rubber snubbers.
 
He was concerned about not enough threads on the bolts for the lug nuts.....the reason for "shaving" the 1/2" off the rubber snubbers.

I have the same problem with my 31x 10.50 MT mud spare with a canyon rim. I think some tires are just a bit too wide. The rubber bumpers stop the inflated tire from having enough threads to mount the tire. I think adding spacers behind the carrier or trimming the snubbers would solve it. I haven’t done it yet but today it may happen and I’ll post it.


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I have the same problem with my 31x 10.50 MT mud spare with a canyon rim. I think some tires are just a bit too wide. The rubber bumpers stop the inflated tire from having enough threads to mount the tire. I think adding spacers behind the carrier or trimming the snubbers would solve it. I haven’t done it yet but today it may happen and I’ll post it.


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Great! Keep us posted....
 
He was concerned about not enough threads on the bolts for the lug nuts.....the reason for "shaving" the 1/2" off the rubber snubbers.
I was saying I would space out the carrier not the rubber piece. 2 flat washers under the lower carrier bolts would bring the bottom of the tire out plenty far. Less time consuming then messing with the rubber.
 
1st pic shows the inside of the tire (inflated to 30 psi) hitting the bottom bumper. Deflating the tire will allow the tailgate to close.

2nd pic shows the depth of the "carrier" from the tailgate to the flat, vertical surface of the carrier. The distance is 7". The level is resting on the top two threaded bolts.

3rd pic shows the gap (2-3/8") when the tire is inflated. This is the distance needed to close the tailgate.

I need another 2-1/2" away from the tailgate to the tire.

I don't think putting 2-1/2" spacers between the tailgate and the carrier is the answer, because that would put a lot more leverage/pressure on the inside of the tailgate with whatever type of bolt and washer set up is in there.

I'm wondering if a wider/deeper carrier is available? One that is 9-1/2" wide/deep as opposed to 7".

If a wider/deeper carrier is not available, the best idea I can come up with is

Any & all thoughts are appreciated.

Chief