Sponsored

Small Spare Tire

RockyMtnHigh

Well-Known Member
First Name
Corey
Joined
Aug 10, 2018
Threads
17
Messages
369
Reaction score
532
Location
Erie, Colorado
Vehicle(s)
2018 JL Rubicon - Punk'n Orange
I see a lot of pictures of people who upgrade their 4 main (on the ground) rims and tires to a larger size, but leave the spare stock. Obviously its a cost save, to make the spare match would easily be $500 to $1000. But what happens when you need the spare? Has anybody driven with an uneven setup? Say a 37 and 33 on the same axle. There will be flex, and you'll probably be riding on the ridges of the tires. Would a setup like this harm your diff? Pull to one side?
Sponsored

 

IPvFletch

Well-Known Member
First Name
Kevin
Joined
Aug 26, 2018
Threads
12
Messages
518
Reaction score
360
Location
ATX
Vehicle(s)
JLUSS
I think flex is less of an issue, but the real issue is your wheels will be rotating at differrent speeds due to the difference in size, this puts more strain on your axle/differential, and this is how you break things. You can't even deflate the larger tire because the diameter still won't change.

Is that really that bad paying 25% more for a 5th wheel/tire? You don't really NEED the tailgate reinforcement for just mall crawling, but it's nice peace of mind while off-roading.

Or you could do spare tire delete and just have a plan B lined up if you get a flat...
 

robplumm

Well-Known Member
Joined
Aug 14, 2017
Threads
0
Messages
141
Reaction score
74
Location
Newport News, VA
Vehicle(s)
2012 JKUR in Dozer
As long as it's not in 4wd...should be....ok-ish?

Can cause some bad issues in 4wd...

ETA: One of my big pet peeves in the Jeep community is seeing that "donut" spare when ppl upgrade their tires.
 

Sponsored

OP
OP
RockyMtnHigh

RockyMtnHigh

Well-Known Member
First Name
Corey
Joined
Aug 10, 2018
Threads
17
Messages
369
Reaction score
532
Location
Erie, Colorado
Vehicle(s)
2018 JL Rubicon - Punk'n Orange
I think flex is less of an issue, but the real issue is your wheels will be rotating at differrent speeds due to the difference in size, this puts more strain on your axle/differential, and this is how you break things. You can't even deflate the larger tire because the diameter still won't change.

Is that really that bad paying 25% more for a 5th wheel/tire? You don't really NEED the tailgate reinforcement for just mall crawling, but it's nice peace of mind while off-roading.

Or you could do spare tire delete and just have a plan B lined up if you get a flat...
"Plan B"

 

OffRoadWarehouse

Well-Known Member
First Name
John
Joined
May 9, 2018
Threads
13
Messages
154
Reaction score
132
Location
San Diego, CA
Website
www.offroadwarehouse.com
Vehicle(s)
2018 Jeep JL
Occupation
Jeep, Shock, Suspension, and Export Specialist
Vehicle Showcase
1
The main thing is it restricts your use of the spare. You can ONLY use it on the rear because you cant have your steering axle having 2 different diameters for steering ability. That means if you get a front flat, you need to rotate one of your full size rears to the front, and then put the spare on the back. That's a lot of extra work!

The rear end can handle having 2 different diameters (AT LOW SPEEDS) but its still not ideal because now your differential is not going to proportion torque to the wheels correctly or efficiently. As long as you arent driving quickly, or offroading it hard, you will make it out.

So you can definitely run a small spare but you create a lot of issues for yourself
 

BillG

Well-Known Member
First Name
Bill
Joined
Mar 12, 2018
Threads
10
Messages
2,067
Reaction score
4,239
Location
Middle Tennessee
Vehicle(s)
2018 Sting Gray JLUR / 15 Harley Tri glide / 50 Dodge Rat pickup
If you off road, it’s easy to damage a tire in a place where you need 4wd or lockers. Mismatched sizes can cause drivetrain stress. If you are only using it on the road, and only use the spare to get to a tire shop for repairs, you’ll be fine. No different from those little spares they put in cars sometimes .
For the best look though, have them all the same.
 

WranglerMan

Well-Known Member
First Name
Will
Joined
May 8, 2018
Threads
100
Messages
3,384
Reaction score
2,693
Location
Katy Texas
Vehicle(s)
2018 Wrangler JLU Sahara
Occupation
Gas Pipeliner
Vehicle Showcase
1
I purchased 5 new wheels and tires when I went to the 17” wheel and 315’s and I just completed my first 5 tire rotation and plan on ding a 5 tire rotation, in my mind there is no sense in only getting 4 tires, now if you wanted to say get the same sized wheel but just a painted rim as in cheap and then a cheap tire of comparable size t9 what you run on the ground and never use in except in an emergency then maybe that would be ok as you can always get a tire cover so it does not look goofy but for me it’s 5
 

WXman

Well-Known Member
Joined
Mar 1, 2017
Threads
61
Messages
2,855
Reaction score
3,076
Location
Central Kentucky
Vehicle(s)
2018 Wrangler Unlimited
Occupation
Meteorology and Transportation
I've had a flat twice in 23 years. I'll take the chance on never needing my spare.

IF I need it, I'll put it on the rear and deflate the opposite side enough to get to a service station.
 

Zazoh

Well-Known Member
First Name
Brian
Joined
Sep 30, 2018
Threads
9
Messages
1,396
Reaction score
6,027
Location
San Antonio TX
Vehicle(s)
2018 JLU Rubicon Sting-Gray
Occupation
Software Engineer
Most modern automobiles have a smaller spare. Have to move two tires if you get a front flat. It would be irresponsible to go on a long offload trip without one, but day to day driving? Eh, you'll do fine.
Sponsored

 
  • Like
Reactions: J0E
 



Top