Today I was out playing around on some newer trails I haven't been on before ... difficult trails maybe a level 7 Jeep trail. I have not been up through there before because my Kuruza wouldn't make it with just A-TRAC and 35" tires. After I had Zuk do a nice job of stuffing 4.88s and front and rear e-lockers in my diffs I was curious about the capability advantages (if any) over just A-TRAC. Note: I also have the 3.12 low-range and 1.1 high-range transfer case gears.
First time on a difficult trail. For those in AZ think Evis ... Ajax Mine ... Smasher Canyon or Highway to Hell, maybe one level up from Charouleau Gap. Or in Colorado think Holy Cross, Grizzly Lake, Iron Chest, or Coon Hollow. So relatively serious trials where you are gonna get some body damage.
The trail I was on today, down here in Mexico, got pretty gnarly much faster than I anticipated ... a cliff on one side and off-camber erosion ... no place to turn around so just got to keep going. I had locked the center, front, and rear diffs and was in low range 1st gear attempting an obstacle, left-hander up maybe a 40-degree incline, not more than ten feet tall, and with a blind backside. I stopped, walked it ... then carefully proceeded forward to see if I had enough breakover to make the obstacle without getting hi-centered. I was creeping, very slowly, and the front was very light, maybe I had a little wheel lift but could not get enough traction even at 7 psi. (I have beadlocks).
The strangest thing happened ... as all four wheels started to just rotate and slowly spin I thought I saw my A-TRAC light come on - but in yellow???? I wasn't sure, had my attention elsewhere as on the blind side of the obstacle there is a 30 feet hole just outside of where my driver's front tire would hopefully track. Didn't matter because I wasn't getting up and over it. I tried another line, cautiously and slowly and the same thing, I thought my A-TRAC engaged again. I double check that my center diff lock was on. Both lockers were engaged, I could feel it. But as soon as I got a little wheel lift, maybe one or both of the front wheels momentarily off the ground is when I felt something. I decided not to try and bump it up the obstacle, that's how I have bought myself many axles. So I did a 72-point turn and went back down the mountain.
I remember before the lockers, in the sand at Glamis, I could not make it up Oldsmobile Hill with A-TRAC ... it just bogged me down no matter what. I had to run through different strategies, and finally, after not even getting close in Low Range, I tried Hi Range but bogged down in 2nd as my truck is underpowered. I figured out that by dropping the shift lever into 1st Hi Range and with center diff lock on, the A-Trac would stop working after about 3000 RPM and I made it up the hill. But it seemed that sometimes that A-TRAC would still kick in even with the center diff locked??? Am I imagining things? I read that they completely revamped the ATRAC for the 06-07 model year with some other nonsense with the ABS and ESC Electronic Brake Force Distribution Control and whatnot, so it has been difficult to find another VVTI driver with similar experiences.
Of the changes in A-TRAC in Low Range it is supposed to not function in 1st gear, only if you start out with the gear selector in 2nd, 3rd or 4th (no 5th in Low Range) - and even if it drops into 1st the A-TRAC will continue to work. Steady throttle application is key as we all know but under 3000 RPMs as it disengages after that. I have seen ATRAC engage in both low and high ranges but did NOT expect it to be able to engage with all three lockers engaged in Low Range. Am I smoking crack?
I will head to a moderate trail with some difficult obstacles outside Tucson this weekend (thinking Chivo Falls, Three Feathers, etc) Sunday and will try and take a video. I am still not 100% sure it was the A-TRAC light flashing but in yellow, I was focused on not rolling off the side of the mountain. But there is something awry and maybe the A-TRAC doesn't like the lockers and there is just enough driveline slop to move the front wheels an inch more and it starts trying to engage? I don't know everything feels pretty tight, all new well pretty much everything has been rebuilt under the truck.
Hoping I can add to this thread and provide some information for anyone else with A-TRAC thinking about doing lockers, the differences in capabilities, costs, or any other information I could share. In the meantime I wanna figure out what / why / if A-TRAC is activating at extreme angles while triple-locked.
Zuk, Overland Cruisers, Cruiser Outfitters, East Coast Gear Supply and Revolution Gear were all excellent to work with - especially Zuk, Onur and Kurt.
First time on a difficult trail. For those in AZ think Evis ... Ajax Mine ... Smasher Canyon or Highway to Hell, maybe one level up from Charouleau Gap. Or in Colorado think Holy Cross, Grizzly Lake, Iron Chest, or Coon Hollow. So relatively serious trials where you are gonna get some body damage.
The trail I was on today, down here in Mexico, got pretty gnarly much faster than I anticipated ... a cliff on one side and off-camber erosion ... no place to turn around so just got to keep going. I had locked the center, front, and rear diffs and was in low range 1st gear attempting an obstacle, left-hander up maybe a 40-degree incline, not more than ten feet tall, and with a blind backside. I stopped, walked it ... then carefully proceeded forward to see if I had enough breakover to make the obstacle without getting hi-centered. I was creeping, very slowly, and the front was very light, maybe I had a little wheel lift but could not get enough traction even at 7 psi. (I have beadlocks).
The strangest thing happened ... as all four wheels started to just rotate and slowly spin I thought I saw my A-TRAC light come on - but in yellow???? I wasn't sure, had my attention elsewhere as on the blind side of the obstacle there is a 30 feet hole just outside of where my driver's front tire would hopefully track. Didn't matter because I wasn't getting up and over it. I tried another line, cautiously and slowly and the same thing, I thought my A-TRAC engaged again. I double check that my center diff lock was on. Both lockers were engaged, I could feel it. But as soon as I got a little wheel lift, maybe one or both of the front wheels momentarily off the ground is when I felt something. I decided not to try and bump it up the obstacle, that's how I have bought myself many axles. So I did a 72-point turn and went back down the mountain.
I remember before the lockers, in the sand at Glamis, I could not make it up Oldsmobile Hill with A-TRAC ... it just bogged me down no matter what. I had to run through different strategies, and finally, after not even getting close in Low Range, I tried Hi Range but bogged down in 2nd as my truck is underpowered. I figured out that by dropping the shift lever into 1st Hi Range and with center diff lock on, the A-Trac would stop working after about 3000 RPM and I made it up the hill. But it seemed that sometimes that A-TRAC would still kick in even with the center diff locked??? Am I imagining things? I read that they completely revamped the ATRAC for the 06-07 model year with some other nonsense with the ABS and ESC Electronic Brake Force Distribution Control and whatnot, so it has been difficult to find another VVTI driver with similar experiences.
Of the changes in A-TRAC in Low Range it is supposed to not function in 1st gear, only if you start out with the gear selector in 2nd, 3rd or 4th (no 5th in Low Range) - and even if it drops into 1st the A-TRAC will continue to work. Steady throttle application is key as we all know but under 3000 RPMs as it disengages after that. I have seen ATRAC engage in both low and high ranges but did NOT expect it to be able to engage with all three lockers engaged in Low Range. Am I smoking crack?
I will head to a moderate trail with some difficult obstacles outside Tucson this weekend (thinking Chivo Falls, Three Feathers, etc) Sunday and will try and take a video. I am still not 100% sure it was the A-TRAC light flashing but in yellow, I was focused on not rolling off the side of the mountain. But there is something awry and maybe the A-TRAC doesn't like the lockers and there is just enough driveline slop to move the front wheels an inch more and it starts trying to engage? I don't know everything feels pretty tight, all new well pretty much everything has been rebuilt under the truck.
Hoping I can add to this thread and provide some information for anyone else with A-TRAC thinking about doing lockers, the differences in capabilities, costs, or any other information I could share. In the meantime I wanna figure out what / why / if A-TRAC is activating at extreme angles while triple-locked.
Zuk, Overland Cruisers, Cruiser Outfitters, East Coast Gear Supply and Revolution Gear were all excellent to work with - especially Zuk, Onur and Kurt.
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