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svpdiesel
07-23-2003, 09:16
Does anyone here know if the Allison can be locked in 4th without a tech-2? would like to run my truck on the local Cat dealer's chassis dyno, but he doesn' have a tech-2, and the truck downshifts without it. Any info would be appreciated.
Thanks
Steve

mackin
07-23-2003, 09:21
Find a friendly with a Tech II ...... :(
OD lock out will only help in a up shift ..... Tech II only once the dyno is loaded,to stop a down shift ......

Good Luck .....

Mac

SoMnDMAX
07-23-2003, 10:34
Try locking the cruise on at about 40 MPH before opening up the throttle, tow haul on, fourth locked out. My truck will not downshift out on the highway if you do this, so maybe (BIG maybe) it will not downshift on the dyno. I have not tried this on the dyno though. Worth a try if you cannot find a Tech II.

Makes for good smoke shows!!

svpdiesel
07-23-2003, 12:25
SoMn- thanks, I'll try it...
Mack- can you lend me yours? :D

svpdiesel
07-23-2003, 17:51
SoMn- it works on my truck too- so I'll give it a try on the dyno. This is a hydraulic brake dyno, and will allow us to run it at any or every rpm rang we want to see, so I'll try and start it as low as possible- 1200 would be nice- and go up in 200 rpm increments. We can then hold it at the selected rpm until the reading stabilizes, and I should be able to get real boost, egt and torque numbers for every rpm we test at.
The Cat guys have never run a "little" truck like this, so they are trying not to laugh at me. I hope to surprise the miserable turds :D :D

mackin
07-23-2003, 20:21
svpdiesel

Let us know if it works, loaded dyno foot to the wood in 4th T/C locked ..... Feeling the near stall load, good luck on a no down shift, but worth a try ......

How you gonna keep it from engaging 5th, right quickly with the Juice ??


Mac http://forums.thedieselstop.com/ubbthreads/images/graemlins/shrug.gif

SoMnDMAX
07-23-2003, 22:52
Originally posted by mackin:
[QB] svpdiesel

How you gonna keep it from engaging 5th, right quickly with the Juice ??


With fourth locked out, the truck shouldn't shift to fifth. The engine should run right up to governed speed, about 3450 RPM.

Good luck, hopefully this works for you.

[ 07-23-2003, 10:57 PM: Message edited by: SoMnDMAX ]

mackin
07-24-2003, 06:49
Originally posted by SoMnDMAX:
</font><blockquote>quote:</font><hr />Originally posted by mackin:
[QB] svpdiesel

How you gonna keep it from engaging 5th, right quickly with the Juice ??


With fourth locked out, the truck shouldn't shift to fifth. The engine should run right up to governed speed, about 3450 RPM.

Good luck, hopefully this works for you. </font>[/QUOTE]Momentary laps of concentration .....

Forgot 03's come with the fancy smancy dual purpose T/H button OD lock out ...

It happens ...


Mac :D :D :D

svpdiesel
07-24-2003, 09:33
Haven't made it to the dyno yet, but testing on a big hill, it will downshift at WOT if revs are below about 2200. On flat ground without a big load, it stays in 4th. Drat! Thought we had good trick going here... so, I'll have to find a tech-II somewhere.
Thanks for everyone's input- I will post results when I get them.
Steve