Allison Neutral Start Back-Up (NSBU) Switch

[Turbo Al]

I read a lot of complaints on the Forum so I though I would add a well done to MorePower.

NSBU
Well it is about time I got my hands dirty fixing this truck. The "OLD STYLE" -- Black one -- died on my truck and Thanks to MorePowers "HOW TO" procedure I got it up and running in less than 25 mins once I got the part.
O yea thanks for nothing Chev dealers (stealers) for the $350.00 quote for the re.& re. They wanted a whopping $250.00 just for the switch! Went directly to Allison for the part @ $95.00.

So Jim IOU -- thanks

BTW -- Jim there is a little nipple between the two electrical plug in's --- for ventalation?? should we be sticking a hose on this and running it into the cab??

Al

PART 2 The Autopsy :eek:

Well you just have to know I couldn't let dead dogs lie.
Drilled out the 11 rivets and pulled it apart. No corrossion of any kind -- mostly made of aluminium, SS and a small bit of copper and full of dielectric grease. Very little water inside at all. It does look like the electrical connections were covered with some kind of hard clear matterial (silicone??) that may have hardened up to the point of making poor contact with the plug in's.
This unit had 32,000 miles on it.
Al

[ 10-26-2004, 03:14 PM: Message edited by: Turbo Al ]

[ZL-1]

Do you remember the part number from Allison? Thanks

[More Power]

pn-29540479 is valid for either a GM part or from Allison (http://www.allisontransmission.com/locator/).

My '01 still as the black module, and it is still working fine. However, I did use the new tan colored NSBU when getting the Project truck (http://www.thedieselpage.com/features/project2-16.htm) up and running.

I suspect the vent on the new NSBU should be left as is. If you install a hose, be care about routing, and be aware that if the hose collects condensation, it could allow more moisture to find its way into the module than it would otherwise without a hose.

MP

[ZL-1]

Part no 29540479 at my local Allison dealer sells for $52.00 plus tax. Thanks for the part no.

[OC_DMAX]

What a price spread Chev = $250 and Allison = $52. Even at $52, I'll bet their still making some profit (just not an obscene profit).

Too bad we don't have a source of $100 injectors. This whole injector thing would be a non-issue (from a cost perspective).

These parts must be resold several times within GM Divisions before making it to the dealer. Each GM Division marking the part up 50% to cover their overhead.

[Turbo Al]

Jim you should really put one of the tan ones in your truck. My trans is performing better than when it was new. No funny bumps or shifting problems, just solid on time shifts.
Al

[ZL-1]

When replacing the NSBU, is it simple to replace it, just a simple swap? Thanks.

[christo]

Yesterday, when passing on a two lane highway, the Allison in my 2001 K2500 made what should have been a shift from 5th to 4th.
Instead it went from 5th to neutral.
I manually shifted to neutral then back Drive and all was OK and has been since.

Is this symtimatic of a faulty NSBU switch or something more serious?

I was in traffic and didn't think to look to see if the shift indicator was still lit.

Any suggestions?

Christo

[Turbo Al]

ZL-1
I just followed More Power's how to in the 2003 Feature articles and Product reviews (comes with Membership) and had no problems. Yes it is an almost identical part.
Al

[ZL-1]

Thanks Turbo Al, it looked like a simple swap. Will put it on this week, a little cool out, but you gotta do what you gotta do. Thanks again.