Well.... I've had a pretty good run with just ATRAC for a long time. I guess my time was up. I broke the R&P yesterday on Red Cone.
I was slow climbing over some large boulders, I *think* what I did was hang up the rear a little, and when I added power to climb, the right front wheel went in the air, ATRAC searched for power at the same time as the right front tire hit the next big rock and grabbed. I thought I heard plastic rip or snap, that must have been the pinion gear spinning....although I didn't know it at the time. Maybe bad luck, maybe I did something wrong. I don't feel like I was rushing, but maybe I was? I was the tail gunner and last in line, so no one else was there to hear it. I backed up, and cleared the rocks without issue. The trail is nothing but rocks at that point, so finding clunks is hard because everything clunks from the terrain.
The 35's coupled with the lower psi and big lugs of mud tires were just a little too much I guess. They grab a little too well and unfortunately, the weak link in the 100 is the ring and pinion gears. Even the newer ones. (Mine is 2004)
Not too much further (actually during the dicey decent off the top) I felt a little clunk/clunk. Thankfully, I was able to descend the steepest part without something locking up and me sliding 2000 feet to my sure demise!
Time for my third front diff isolation, but first on my own truck. Found a spot at the end of the trail....locked the CDL, pulled the drive shaft, still had the noise. Pulled the flanges.... no noise. I drove home in 2wd with Romer following me. Rising Sun leaves no one behind and thanks to the guys for staying with me while I got buttoned up! The noise was never super loud or obnoxious. I even had a few others drive my truck or stand next to it while I drove by. Almost un-noticeable unless you're familiar with how your truck sounds/feels.
Pretty easy to figure out now, I was frustrated yesterday and didn't take a minute to think about what I needed to pinpoint the problem. Isolate the problem first which is what I did by pulling the drive shaft, then the flanges. Then work down the list of possibilities.
When I grab the tail flange of the differential and spin it, every rotation has a bind that I can get through by turning a little harder (that would be the broken teeth on the pinion gear) and at 4.1 turns of the flange, it totally binds up. That would be the broken teeth on the ring gear meeting the broken teeth on the pinion gear. 4.1 turns = 4.10 gears. That's where my break happened. Or, another way to think of it would be $700 for every turn of the pinion gear
crybaby
I hope this might help someone else try and figure out whether it's their diff/gears or something else. FWIW, this morning I installed the flanges and the driveshaft, raised the front in the air and spun the tires. So, only the spider gears would spin. One tire rotates in one direction, the other tire rotates in the opposite direction. No binding, so my spider gears are intact.
I'm going to drain the fluid today and see what I find, but I know what it's going to be..... teeth. It's a really bad time for this to happen. Both for the financial hit and the fact that 100s in the Hills is 10 days away.
To add some sprinkles to that sweet dish, a guy on a motorcycle smashed into me on the trail and dented me all up. It wasn't my best day, but sometimes a little perspective goes a long way. I made it home, my family is healthy and happy and in the grand scheme of life, it's not the worst thing that could happen and it can be fixed.
Another way for me to think about it is, I can now make this the strong point of the front end and something else will become the weaker link. A CV axel or U Joint is easier and far less expensive than doing this repair twice.
I was slow climbing over some large boulders, I *think* what I did was hang up the rear a little, and when I added power to climb, the right front wheel went in the air, ATRAC searched for power at the same time as the right front tire hit the next big rock and grabbed. I thought I heard plastic rip or snap, that must have been the pinion gear spinning....although I didn't know it at the time. Maybe bad luck, maybe I did something wrong. I don't feel like I was rushing, but maybe I was? I was the tail gunner and last in line, so no one else was there to hear it. I backed up, and cleared the rocks without issue. The trail is nothing but rocks at that point, so finding clunks is hard because everything clunks from the terrain.
The 35's coupled with the lower psi and big lugs of mud tires were just a little too much I guess. They grab a little too well and unfortunately, the weak link in the 100 is the ring and pinion gears. Even the newer ones. (Mine is 2004)
Not too much further (actually during the dicey decent off the top) I felt a little clunk/clunk. Thankfully, I was able to descend the steepest part without something locking up and me sliding 2000 feet to my sure demise!
Time for my third front diff isolation, but first on my own truck. Found a spot at the end of the trail....locked the CDL, pulled the drive shaft, still had the noise. Pulled the flanges.... no noise. I drove home in 2wd with Romer following me. Rising Sun leaves no one behind and thanks to the guys for staying with me while I got buttoned up! The noise was never super loud or obnoxious. I even had a few others drive my truck or stand next to it while I drove by. Almost un-noticeable unless you're familiar with how your truck sounds/feels.
Pretty easy to figure out now, I was frustrated yesterday and didn't take a minute to think about what I needed to pinpoint the problem. Isolate the problem first which is what I did by pulling the drive shaft, then the flanges. Then work down the list of possibilities.
When I grab the tail flange of the differential and spin it, every rotation has a bind that I can get through by turning a little harder (that would be the broken teeth on the pinion gear) and at 4.1 turns of the flange, it totally binds up. That would be the broken teeth on the ring gear meeting the broken teeth on the pinion gear. 4.1 turns = 4.10 gears. That's where my break happened. Or, another way to think of it would be $700 for every turn of the pinion gear
crybaby I hope this might help someone else try and figure out whether it's their diff/gears or something else. FWIW, this morning I installed the flanges and the driveshaft, raised the front in the air and spun the tires. So, only the spider gears would spin. One tire rotates in one direction, the other tire rotates in the opposite direction. No binding, so my spider gears are intact.
I'm going to drain the fluid today and see what I find, but I know what it's going to be..... teeth. It's a really bad time for this to happen. Both for the financial hit and the fact that 100s in the Hills is 10 days away.
To add some sprinkles to that sweet dish, a guy on a motorcycle smashed into me on the trail and dented me all up. It wasn't my best day, but sometimes a little perspective goes a long way. I made it home, my family is healthy and happy and in the grand scheme of life, it's not the worst thing that could happen and it can be fixed.
Another way for me to think about it is, I can now make this the strong point of the front end and something else will become the weaker link. A CV axel or U Joint is easier and far less expensive than doing this repair twice.
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Hopefully you can figure out an economical situation to get back on the road quick!
