What is the normal amount of converter slippage that you should see. I know theoretically when the converter is locked you should see no slippage.
Allison 6sp: Converter Slippage
- Thread starter Duramax 6.6L
- Start date
I think maximum acceptable is 25 rpm's and 35-50 rpm's will eventualy set a code under stock hp conditions. IMO with big power that 25 rpm slip will become way bigger after time.
A good multi disc converter will show either 0 rpm slip or actualy a minus number if you check it with a Tech 2. There is no such thing as a minus slip but the Tech 2 is programed to see some kind of slip.
I have a used triple disk in my truck, it is showing between 5 and 15 rpm with a 500 HP tune at a steady cruise of 70 mph. Might be time for a new converter.
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What did you read that slip with? A quality triple disc is not know to slip. certain converters will notch the billet cover and begin to bind on TCC apply. If you checked the TCC slip with anything other than a Tech 2 or Allison DOC I don't know if you are ready correctly.
I read it with EFI Live, while I was logging some data, with about 20 minutes of driving at 70 mph, it showed a constant reading of 5 - 15 rpm slippage.
if I'm reading the same numbers you are, thats about what my 6gun was reading with the cruise set at 70 on the highway. saw as high as 20. but, it said 'tcc percent on - 0' iirc.
The 4L85E will set a TCC sllip code a whole lot faster than an Allison. If you haven't seen a code you are probably not slipping the converter clutch.
that was in the lbz truck
edit - but good to hear that! havent seen a code in the van ever, and the 6gun sounded a 'tuner fault' trans slip when i dyno'ed the truck but nothing on the factory computer.
What's the most miles you've seen on an Alli?
edit - but good to hear that! havent seen a code in the van ever, and the 6gun sounded a 'tuner fault' trans slip when i dyno'ed the truck but nothing on the factory computer.
What's the most miles you've seen on an Alli?
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Mike,
Wondering what all this means about the P0777 code. This is the code that I got nailed with that I spoke about in PM with you yesterday.
On the scanner it read, "Pressure Solenoid Valve B stuck" Is this the same valve that is "modified" with the TG Jr.?
It stuck in 4th gear. It would go any speed the rpm allowed. However, when i exited the near ramp it stayed in 4th and would not downshift. When i parked, as I moved the gear shift from P to R it said gear range inhibited and the same with D. It would not move at all.
Made a call, the guy said cycle the key 6 times or so. I did, not it is running "fine". Ya, I am in tippy-toe mode right now as that I got freaked out.
Can you help me understand this code? and, perhaps what happened to my converter or trans? Should I return to stock?
P0777 indicates that an off going clutch did not release in time as the on coming clutch was applying. ( tie up ) This indicates that a clutch pack was overpowered. You have done damage but we don't know how much. Time to cut the power back as it will happen again only sooner.
Atleast yours came out of it. My buddies did that pulling his gooseneck home in the 1st setting on his edge and that was the end of it. That was also the first time that trans ever limped with 85K miles. Its now built and he runs EFI live.
just an update to my last reply concerning trans limp on the P0777 code. Even though I have not made very many hard runs WOT up into sixth gear, it has been done a few times with no problems yet. I have done some drag racing on the street, no limp. I have ran about 10, 1/8 mile track passes, even ran an 8.09 with just a Jr....no limp. This weekend I am going go do between 1 and 4, 1/4 mile passes to see if I can get down into the 12s with a stock transmission...see what happens. I know that I am on borrowed time with the stock, but we will just have to see what happens.
