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Discussion Starter · #1 ·
My father has a 2005 D-max with the 5 speed Allison. Back in the beginning of 2019 he went to the USA for a month and on the way down had the P0735 code came up. He was on the interstate onramp getting up to speed pulling a small travel trailer. The trany clunked and went into limp mode. He had it looked at by a trany shop there and they couldn't find a problem with it after many hrs of looking around road testing and could never get it to repeat the code. The conclusion they came up with was the output shaft bearing was worn causing the rear speed sensor to glitch. They changed the bearing with the tail stock and the speed sensor.

Now we are having a similar problem again, though it doesn't clunk ever and it's very random and the code seems to pop up only under load (getting up to speed or pulling a trailer). It's very hard to force it to happen but I have finally caught it when my EFILive scanner was attached.
Water resources Ecoregion Light Nature Water


I know the code comes from to output speed sensor being more than 200rpm different than it should be for the gear it is in. The little dip in the TOS RPM (at the marker) is 209rpm so I'm assuming this is what triggered the code.

My question for all the wise internet folks is. Am I right in think it is still an sensor/electrical issue and not something wrong with the integral valves or clutches in the trany?

This is what the run looked like from stop to stop:
Azure Rectangle Water Slope Font
 

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Welcome to DieselPlace

Here is a thread with some info on the p0735 code: P0735
 

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2007 Klassic CCSB 2500HD. Six-gun w/speedloader, iDash, and EFILive.
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rut ro. Read what Mike said.

 

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Discussion Starter · #4 ·
Thanks for replying

I got to thinking about it more last night and after going over the data again I agree that the problem is the clutch and not an electrical/sensor issue. I was stuck on the fact that the output sensor only had a drop for 23 tenths of a second. After adding the torque data to the graph I found this:
Rectangle Slope Water Font Plot


Basely the trans pulled engine torque (blue) the after it saw the clutch slipping (purple arrow) and applied torque again after the downshift to fourth (green). The output sensor (orange) has the drop in it from the slop of the driveshaft/diff gears/axle splines with the forced gear change down to fourth.

I love data. 🤪
 

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2007 Klassic CCSB 2500HD. Six-gun w/speedloader, iDash, and EFILive.
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Right? As long as it's valid AND you're at all the relevant parts. Increase in RPM with a decrease in torque is only good in helicopters doing autorotations. Pretty cool how the transmission forces the downshift to save itself. Mike L used to and probably still does sell all kinds of kits with bits from mild to wild if you're going to rebuild it yourself. I wish I lived closer to him. I'd have dropped my truck off long ago.
 
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