acme66
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- Plains, Montana
Back and forth the debate rages. I just did it to mine and the difference was astounding. This was a truck that shifted rather well mind you but now? No joke it is better than my wife's SUV. You could set a cup of coffee on the seat next to you, go from 2nd to 1st and not spill a drop. Anyway no need to take my word for it, I did what we do around here and filmed it, you can ride along and see for your self.
https://www.youtube.com/watch?v=B3ccBMMyNuA
Short version, I read up on the fluids Allison recommends for the transmission. I talked with the tec at a Kenworth heavy truck shop. They push the new synthetic which might be worth it for some of you. I took his advice an put in a NAPA branded Premium Heavy Equipment Hydraulic Oil and Transmission Fluid. $54 for 5 gallons, it took about 4. I will update if anything develops long term and I can't hide it from you because if I start sniffing around for a tranny you will know. Now we can all learn together and I will document it.
First glance:
Shifting-oh so smooth, like butter. Hard to feel upshifts and the dreaded downshifting that makes the drivelines ring is gone.
Temp- down 15-20 right off the top. At idol, driving, climbing the pass, wherever it would have been it is now 15-20 less.
Unscientific stuff:
Power- I think the converter might be locking better, it trucked up the pass in one gear higher than I seem to remember it doing before.
Whine- Tranny/transfer whine is much diminished but not gone. That also could be related to changing out the oil in the transfer case.
High/low -Again this might be all the oil change in the transfercase but it slid right in and out in a way it has never done before.
(Transfer case was converted to a houseblend 80/90. Now don't start the EAT THE BRASS rage, that hasn't been true in a decade, ever since they took the sulphur out)
So that is that. If it cooks I will own up and post it here but I don't think it isn't going to. I was on the fence but it took about .5 mile to be converted. I know it isn't what the TM says but it is in line with what the transmission manufacturer says to use. Personally I cringed every time I heard that drivetrain go ka-BAM! Everyone of the arguments used against this switch were valid, maybe as recently as a decade ago but probably longer. Modern oils have at least doubled the lifespan of motors and drivetrain in the last 15 years. To not take advantage of that in something this expensive seems, well dumb. Regardless of what a book says.
Anyway not trying to convince you, just laying out my thought process. I am going to put thousands of miles on this truck in the next 3 months. Hit me up in September and see if I am still a convert. Then you can have some long term test results, or trumpet a big "I told you so".
Ken
https://www.youtube.com/watch?v=B3ccBMMyNuA
Short version, I read up on the fluids Allison recommends for the transmission. I talked with the tec at a Kenworth heavy truck shop. They push the new synthetic which might be worth it for some of you. I took his advice an put in a NAPA branded Premium Heavy Equipment Hydraulic Oil and Transmission Fluid. $54 for 5 gallons, it took about 4. I will update if anything develops long term and I can't hide it from you because if I start sniffing around for a tranny you will know. Now we can all learn together and I will document it.
First glance:
Shifting-oh so smooth, like butter. Hard to feel upshifts and the dreaded downshifting that makes the drivelines ring is gone.
Temp- down 15-20 right off the top. At idol, driving, climbing the pass, wherever it would have been it is now 15-20 less.
Unscientific stuff:
Power- I think the converter might be locking better, it trucked up the pass in one gear higher than I seem to remember it doing before.
Whine- Tranny/transfer whine is much diminished but not gone. That also could be related to changing out the oil in the transfer case.
High/low -Again this might be all the oil change in the transfercase but it slid right in and out in a way it has never done before.
(Transfer case was converted to a houseblend 80/90. Now don't start the EAT THE BRASS rage, that hasn't been true in a decade, ever since they took the sulphur out)
So that is that. If it cooks I will own up and post it here but I don't think it isn't going to. I was on the fence but it took about .5 mile to be converted. I know it isn't what the TM says but it is in line with what the transmission manufacturer says to use. Personally I cringed every time I heard that drivetrain go ka-BAM! Everyone of the arguments used against this switch were valid, maybe as recently as a decade ago but probably longer. Modern oils have at least doubled the lifespan of motors and drivetrain in the last 15 years. To not take advantage of that in something this expensive seems, well dumb. Regardless of what a book says.
Anyway not trying to convince you, just laying out my thought process. I am going to put thousands of miles on this truck in the next 3 months. Hit me up in September and see if I am still a convert. Then you can have some long term test results, or trumpet a big "I told you so".
Ken
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