What did you do to your Cherokee today?
10-28-2016, 12:48 PM
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Year: 1993 YJ Wrangler
Engine: 4.0 I6
It was under so much load that when I took out the fourth driveshaft bolt, the whole assembly jumped, and the Jeep rocked forward and back.
The good news is I just reassembled everything, and the test drive went smoothly. I made sure the nut was torqued to 150lb/ft this time.
Disassembly started with this:
As the last threads came out of the last driveshaft bolt, it jumped to this in the blink of an eye
10-28-2016, 12:52 PM
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Year: 1994
Model: Grand Cherokee
Engine: 4.0
Just bought a set of 31x10.50 KO2s with like 80% tread from a coworker for $400. Going to get them put on today so i can try em out this weekend!
10-28-2016, 02:39 PM
No, I don't lick fish.
I was right! The yoke nut spun off while I was driving...
It was under so much load that when I took out the fourth driveshaft bolt, the whole assembly jumped, and the Jeep rocked forward and back.
The good news is I just reassembled everything, and the test drive went smoothly. I made sure the nut was torqued to 150lb/ft this time.
Disassembly started with this:
Attachment 295778
As the last threads came out of the last driveshaft bolt, it jumped to this in the blink of an eye
Attachment 295779
It was under so much load that when I took out the fourth driveshaft bolt, the whole assembly jumped, and the Jeep rocked forward and back.
The good news is I just reassembled everything, and the test drive went smoothly. I made sure the nut was torqued to 150lb/ft this time.
Disassembly started with this:
Attachment 295778
As the last threads came out of the last driveshaft bolt, it jumped to this in the blink of an eye
Attachment 295779
Sheeeezus..... glad it went back together okay and glad you didn't get hurt in the process. Looks like it was under a pretty decent torque load
10-28-2016, 03:46 PM
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Year: 1993 YJ Wrangler
Engine: 4.0 I6
It all went back together with a couple light taps from a mallet. A quart of fluid, and I was on my way.
10-28-2016, 04:10 PM
No, I don't lick fish.
I was really surprised to see nothing bent or twisted. The splines on the yoke have a little wear on the ends from slipping after the failure, but it only affects about 1/8" on the ends.
It all went back together with a couple light taps from a mallet. A quart of fluid, and I was on my way.
It all went back together with a couple light taps from a mallet. A quart of fluid, and I was on my way.
Lookin' good... what PSI you runnin'?
10-28-2016, 04:13 PM
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Year: 1994
Model: Grand Cherokee
Engine: 4.0
10-28-2016, 04:30 PM
No, I don't lick fish.
Rule of thumb is, the larger the tire, the less PSI you need to run on the highway. Door sticker says 33 psi for 215/75r15s on an XJ... not sure what your ZJ will say, but you should be at less than that.
Start with the PSI on the door and then take a piece of chalk and draw a line across the tread surface of all four tires. Do some normal driving for a few miles. If the chalk wears evenly, you're at the right PSI. If it's more worn in the middle, take some air out.
I air down to 10 PSI on the trails and I'm on 15x8s.... you should be able to do about that much with 10.5" wide tires on those 7" wide wheels.
10-28-2016, 04:36 PM
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43 is way too high and I'm almost positive that exceeds the max pressure on the sidewall - which shouldn't be used on a jeep regardless.
Rule of thumb is, the larger the tire, the less PSI you need to run on the highway. Door sticker says 33 psi for 215/75r15s on an XJ... not sure what your ZJ will say, but you should be at less than that.
Start with the PSI on the door and then take a piece of chalk and draw a line across the tread surface of all four tires. Do some normal driving for a few miles. If the chalk wears evenly, you're at the right PSI. If it's more worn in the middle, take some air out.
I air down to 10 PSI on the trails and I'm on 15x8s.... you should be able to do about that much with 10.5" wide tires on those 7" wide wheels.
Rule of thumb is, the larger the tire, the less PSI you need to run on the highway. Door sticker says 33 psi for 215/75r15s on an XJ... not sure what your ZJ will say, but you should be at less than that.
Start with the PSI on the door and then take a piece of chalk and draw a line across the tread surface of all four tires. Do some normal driving for a few miles. If the chalk wears evenly, you're at the right PSI. If it's more worn in the middle, take some air out.
I air down to 10 PSI on the trails and I'm on 15x8s.... you should be able to do about that much with 10.5" wide tires on those 7" wide wheels.
10-28-2016, 04:44 PM
No, I don't lick fish.
Gotcha. Either way, too much air for a Jeep on Light Truck tires. You'd wear the centers of those tires out faster than a pencil eraser.
10-28-2016, 04:52 PM
No, I don't lick fish.
NAH.... There's no possible way in the world they could know the perfect PSI for every vehicle they put tires on. Heck, that's why the chalk-line tests exist... because Tire Manufacturers don't even take the time to calculate all that out.
10-28-2016, 06:25 PM
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Year: 1993 YJ Wrangler
Engine: 4.0 I6
But on the flip side, there's a lot of incompetent people at tire shops. My 37s were aired up to 45psi after I had them mounted and balanced
10-28-2016, 08:07 PM
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Year: 1999
Model: Cherokee
Engine: 4.0
If you want a specific pressure you have to state to the person installing. Not many people know what they want but when you recommend pressure for them, they get upset that it's below the pressure on the sidewall. That's why you typically end up with higher pressures.
10-28-2016, 08:24 PM
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Year: 1993 YJ Wrangler
Engine: 4.0 I6
You'd be surprised how many people are adamant about using what the tire says on the sidewall. It's now almost standard to just go 5 to 10 pounds less when installing other people's tires.
If you want a specific pressure you have to state to the person installing. Not many people know what they want but when you recommend pressure for them, they get upset that it's below the pressure on the sidewall. That's why you typically end up with higher pressures.
If you want a specific pressure you have to state to the person installing. Not many people know what they want but when you recommend pressure for them, they get upset that it's below the pressure on the sidewall. That's why you typically end up with higher pressures.