LMTV shifting issue

[Third From Texas]

make darn sure your batteries/charging system is 100%. as I found out the Allison is super temperamental to incorrect voltage...

It's funny how many of these issues pop up when it gets cold and the batteries often get weak...

 

[tennmogger]

Please be aware that one disconnect switch cannot disable both the 12 and 24 volt circuits. Just disconnecting the ground still leaves high current available from the positive of the 12v circuits/devices and the positive of the 24v devices. For example, working on the Power Distribution Panel, or the Polarity Protection Device, there is high current 12v just waiting for you to short it.

 

[chucky]

If you have anymore gliches on the backside of your spare tire under the hyd pump box is a polarity protection module ppm and it has 4 studs sticking out the bottom 2 are 24v the top 2 are 12v my bottom lug basicly roted almost all the way thru and my transmission was going crazy jumping in and out of gear under power and since the post was roted i just put the 2 24v cables on the next post up i just dont have any protection on hooking up battery cables wrong on the 24 side so you might give that a look see and clean all those post and cables but just 1 at a time so you dont get any cables in the wrong spots and be gentle on getting those nuts to back off you can soak them in some good penetrating oil to help cut through the rust on them ! It fixed my trans problems

 

[Ronmar]

Please be aware that one disconnect switch cannot disable both the 12 and 24 volt circuits. Just disconnecting the ground still leaves high current available from the positive of the 12v circuits/devices and the positive of the 24v devices. For example, working on the Power Distribution Panel, or the Polarity Protection Device, there is high current 12v just waiting for you to short it.

Yep, this isn’t for safety, it is for unloading the batteries as it will disable the 12 and 24v circuits. For safety you need to also lift the 12V or 24V leads…