Turricane II
NAXJA Forum User
- Location
- San Francisco
was just wondering if one could get away with putting 30/9.5/15's on a stock '89 XJ w/o worrying about the tranny or messing with the speedometer? THanks
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30" tires?
- Thread starter Turricane II
- Start date
Really doubt you would have any problem with the trans, and the speedo diff would be so small, the radar gun wouldnt even bother with it 
But Im not sure about fender clearance to be honest with you, I was told a while back that 29s were the biggest you could go stock, dunno if its true or not.
But Im not sure about fender clearance to be honest with you, I was told a while back that 29s were the biggest you could go stock, dunno if its true or not.
- Location
- Terra Firma
I have an '88 with a stock suspension. I run 30x9.50-15s when I go wheeling, and I have no problems.
Your stock tire size on an '89 was probably 205/75 or 215/75. The jump from 215s to 30s is about 6%. That means when your speedo says 60 MPH you are actually going 60 + 6% = 63.6 MPH. That's assuming your speedo was perfectly accurate with 215s -- which is probably not the case. The stock speedo always seems to read a couple of percent faster than you're really going, so the true error when you go up to 30" tires is probably closer to 4% to 5%.
Your stock tire size on an '89 was probably 205/75 or 215/75. The jump from 215s to 30s is about 6%. That means when your speedo says 60 MPH you are actually going 60 + 6% = 63.6 MPH. That's assuming your speedo was perfectly accurate with 215s -- which is probably not the case. The stock speedo always seems to read a couple of percent faster than you're really going, so the true error when you go up to 30" tires is probably closer to 4% to 5%.
CaptTrev
NAXJA Forum User
- Location
- Long Island
I ran 30/9.5's on my old 87 completely STOCK for a few years. and i wheeled it all over the place with minimal problems. BUT i had the sway bars connected.
i DO however, remember (on full hard over turns) some minor rubbing on the lower control arms....but no big deal
i DO however, remember (on full hard over turns) some minor rubbing on the lower control arms....but no big deal
FreemansXJ
NAXJA Forum User
- Location
- Spring Hill, Ks
I am running 30/9.5/ 15's on my 99XJ. I originally put them on with the stock suspension. It would slightly rub if it was really tweaked. I installed the 2 inch spacers and add-a-leafs and have had no problems.
John
John
Drewlee77
NAXJA Forum User
- Location
- Abilene, TX
Actually, upgrading to 30" tires fixed my speedo. I used a GPS to check how far off it was and it was dead-on. I checked it a number of times and it was always PERFECT at 70-75 mph. It's always perfect when i go past those radar signs (like a construction zone or something) as well. All that to say: the only sure way to know how far off it is is to check it.
ThePhantum
NAXJA Forum User
- Location
- Richmond, VA
I put in a 2"BB to clear the 30"s on my '97. To keep 'em off the control arms I went to 3.75' of backspace on the wheels. Had some minor rubbing on the bumper guards, but fixed that with a coping saw and utility knife.
All four wheels stuff perfectly now with no rubbing whatsoever...even at full lock.
My speedo is approx. 5% off. I'm finally gonna get it fixed either this week or next...just gotta get the time.
All four wheels stuff perfectly now with no rubbing whatsoever...even at full lock.
My speedo is approx. 5% off. I'm finally gonna get it fixed either this week or next...just gotta get the time.
8Mud
NAXJA Forum User
- Location
- Central Germany
I have 30X9.50´s MT´s on a stock 88, the only suspension mod is a slightly stiffer shock. I put a washer behind the turn stops and have no control arm rubbing. Have skinned the wheel well liner a few times, but never damaged anything. My 30´s actually measure closer to 29 1/2", and the tread, while a partial wrap around, is slightly beveled or angled at the edge. Like they were made for the XJ. I´m thinking, at just the right angle, they may clip a flare, but hasn´t happened yet. Stock 7" multi spoke (Limited) type cast aluminum Jeep rims.
gr8tires
NAXJA Forum User
- Location
- charlotte, nc
My daughter put some 30r950x15s on her stock "00 Sport 4x4 with no problems. Had some scrape sounds on Uwharrie's easy run, but not out on the street.
In my experience, 30x9.5s in goodyear tires will rub at full lock on 15x7 stock rims.
On 15x8 TJ canyons, NO rubbing whatsoever on XJ or MJ 2WD or 4WD w/ any 30" tire.
30x9.5 MT/Rs on stock 96 XJ rubbed lower control arms at full lock.
as well as 88 MJ, and 86 MJ.
30x9.5 GS-As on stock sagging 85 XJ rubbed lower control arms at full lock.
as well as 87 MJ, (3) 86 XJs, and 88 and 89 MJ.
This is what I know.
I now run 235/75R15 Cooper ATs as much as I can on everything I have.
I ran the 30x9.5 MT/Rs on the 96 XJ and off-roaded with them, no major problems, but got sick of them stuffing...switched to the 235s and did the same stuff, much better.
Teron
On 15x8 TJ canyons, NO rubbing whatsoever on XJ or MJ 2WD or 4WD w/ any 30" tire.
30x9.5 MT/Rs on stock 96 XJ rubbed lower control arms at full lock.
as well as 88 MJ, and 86 MJ.
30x9.5 GS-As on stock sagging 85 XJ rubbed lower control arms at full lock.
as well as 87 MJ, (3) 86 XJs, and 88 and 89 MJ.
This is what I know.
I now run 235/75R15 Cooper ATs as much as I can on everything I have.
I ran the 30x9.5 MT/Rs on the 96 XJ and off-roaded with them, no major problems, but got sick of them stuffing...switched to the 235s and did the same stuff, much better.
Teron
