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Discussion Starter #1
Most of the time whether I'm pulling my 10,000 trailer or not, I'm in
overdrive and the the truck handles steep grades pretty good
keeping up the speed to 60 MPH+

My question is this...... when I put the tranny in 3rd, I will almost
redline if I travel over 50 mph. In 3rd @ 42 MPH, I'm at 2500 rpm.

Is our 3rd geared to low or what's up?
 

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Unlike a normal 4 speed auto where the third is the 1:1 ratio gear, in the 5 speed allison the 4th is the 1:1 ratio gear and fifth the overdrive. So third is rather low. Do a search for gear ratios and you can find the ratios here somewhere, in ask the techs or tsb I think.


Anyway, when you pull it into third you are bypassing 4th entirely and so it probably is revving higher than expected. There is no position on the gear selector for 4th. In the DIY section you can find instructions for installing an overdrive lockout on your 02 so it will stay in 4th, and out of 5th when you want it.


I think this will help if I understood what you were doing correctly.
 

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Nomad, just leave the trans in tow/haul and overdrive. I have towed my 10K Wildcat over 8K miles and have never had a need to shift into anything lower than 4th. I only put it in 4th after it shifts down on a long grade. Later! Frank
 

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Discussion Starter #4
Hi Frank,

Thanks for your comments, but how can I put and keep the
Allsion in 4th unless I install an overdrive lockout?
 

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56Nomad,


I don't think you can do that without installing the OD lockout, that's why they are so popular.


Not sure when GM came to their senses and included that option, but my '04 has it.Edited by: Zeeb
 

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03 is when they started putting that in there. Quite handy.
 

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56Nomad said:
Hi Frank,

Thanks for your comments, but how can I put and keep the
Allsion in 4th unless I install an overdrive lockout?

My question also.


I found that by watching the pyro gauge, I can hit the lockout and go streight into 4th satisfactory.


If I wait for the computer to tell the trans to downshift ~ it downshifts to 3rd for an instant ~ long enuff to hit the rpm limiter and then upshifts to 4th. I've found the lockout method to be easier on the nerves ~ but is manual intervention w/what is supposed to be an automatic trans ~ oh well
 
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