Allison 5sp: Check engine light and codes..

[66FLH]

Ok, so after driving through the hailstorm from hell on the way Home from Albuquerque Saturday evening (had to fix my daughters car), I have a check engine light,P700-708 codes and my tranny is acting really strange...The little indicator light under DRN123 is blinking on and off too.
I already tried clearing the codes to no avail...I know its the NSBU but my question is do I need to replace it or just clean it? The hail was 6-8 in. deep on the Interstate and I'm sure everything got soaked completely...
Has anyone here just cleaned it with contact cleaner and some air?
Truck was running fine before!

 

[Mike L.]

Sounds like a classic NSBU problem. Almost everytime I see P0708 on a 5 speed it is NSBU.

 

[Lb7KID]

happend to me a few ounth ago it prob youer nsbu switch. mine had a hand full of codes tho so the new switch did not fix mine i dont think cleaning youer switch will do much help i no napa sold me a new one for 30 bucks i think

 

[66FLH]

Thanks guys!:hug:

 

[Mike L.]

Thanks guys!:hug:

Did you fix it my friend? Call me if you need me.

 

[66FLH]

Did you fix it my friend? Call me if you need me.

I took it off and blew it out with air but it's still acting screwy...Can you pm me a price on a new one? Dealer quoted me a discounted price of $188.00...

 

[Mike L.]

Buy it from an Alliso dealer or a trans shop. It is the same switch as a 4L80E or 4L60E.
Make sure the trans is in nuetral and do not rotate switch when installing. Just slide it on, bolt it up and fish putting everything else on.

 

[66FLH]

Thanks Mike..I found it in Albuquerque for $70.00 ,not too bad!

 

[Gary Apodaca]

Nsbu

Where in Albuquerque did you find the switch for $70? I have the same problem and called NAPA, they want $238.00. I think I was in the same storm.