I did a search and didn't see this exactly so I thought I'd share. Doing some light upgrades on a very stock 99 TJ. First on the list was 31's and I was lucky enough to find a cheap single to use as a spare.
As I am sure many know that a 31/10.5/15 will not fit on the stock spare carrier and bumps (I had 235/75/15's before) as the tire hits the bumps before the bolts show through the rim. I debated wheel spacers but at $60-100 for a pair and adding an inch I was wary and cheap. It would also mean cutting the old bolts down.
Instead I decided to grind off the spot welds on the stock studs and add some new 2" long bolts (I think - maybe 2.5" - verify for your case). I then tack welded these on (so they don't spin) and cold galvinized them before a coating of tremclad on all the sides that needed it.
I still wanted the rim tight on the carrier plate (like a spacer would have been) so I made a custom 3.625x5.25" plate in 3/4" solid plastic (you could use alum or even wood if in a pinch) and the whole thing worked out great. The tire fits and just clears the 3rd brake light and bumper and with the spacer it just tightens up to the bumps and the spacer. I could probably reduce the spacer another 1/16 - 1/8" to get them tighter on the bumps if I wanted but it doesn't seem enough for a redo.
The biggest benefit was 1) cost - its cheap - the paint was the only expensive bit (luckily I had access to a welder) 2) no mods needed on the bumps/bumper/mount and 3) all other exiting hardware was reused. You might get up to a 33 this way if you also make a plate to raise the 3rd brake light. but it might also hit the lower bumper.
The spacer I made was CNC cut (I run a CNC for work) but you could do them by hand too.
Didn't take great pics but have some attached. The pics just show the concept and the result - the result is underwhelming as it looks like the stock look - but that was exactly the point here. Note the black spacer is 1" as I wasn't sure what I needed and cut both a 3/4" and 1".
As I am sure many know that a 31/10.5/15 will not fit on the stock spare carrier and bumps (I had 235/75/15's before) as the tire hits the bumps before the bolts show through the rim. I debated wheel spacers but at $60-100 for a pair and adding an inch I was wary and cheap. It would also mean cutting the old bolts down.
Instead I decided to grind off the spot welds on the stock studs and add some new 2" long bolts (I think - maybe 2.5" - verify for your case). I then tack welded these on (so they don't spin) and cold galvinized them before a coating of tremclad on all the sides that needed it.
I still wanted the rim tight on the carrier plate (like a spacer would have been) so I made a custom 3.625x5.25" plate in 3/4" solid plastic (you could use alum or even wood if in a pinch) and the whole thing worked out great. The tire fits and just clears the 3rd brake light and bumper and with the spacer it just tightens up to the bumps and the spacer. I could probably reduce the spacer another 1/16 - 1/8" to get them tighter on the bumps if I wanted but it doesn't seem enough for a redo.
The biggest benefit was 1) cost - its cheap - the paint was the only expensive bit (luckily I had access to a welder) 2) no mods needed on the bumps/bumper/mount and 3) all other exiting hardware was reused. You might get up to a 33 this way if you also make a plate to raise the 3rd brake light. but it might also hit the lower bumper.
The spacer I made was CNC cut (I run a CNC for work) but you could do them by hand too.
Didn't take great pics but have some attached. The pics just show the concept and the result - the result is underwhelming as it looks like the stock look - but that was exactly the point here. Note the black spacer is 1" as I wasn't sure what I needed and cut both a 3/4" and 1".
