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jsmiracle
06-29-2007, 10:39
Does anyone know why the GM trucks outfitted with the Allison transmission were given the Allison shallow transmission drain pan?

Clearence doesn't seem like the gain since the spin-on filter hangs down fairly low.....:confused:

FYI, I do a fair amount of towing and considered installing the "deep" or regular drain pan the next time I change fluid.

Thanks in advance,
Jim M.

P.S. I just realized that this post may be better suited for the "Towing" thread.

jbplock
06-29-2007, 12:49
Jim,

I believe clearance is the reason for the shallow pan on our trucks. The deep pan on my 03 hangs slightly below the frame line. IIRC fluid capacity increases about two quarts. After the install I noticed the tranny temp would rise slower but once it was hot temperatures behaved about the same as with the stock pan.

:)

mark45678
06-30-2007, 07:53
Does anyone know why the GM trucks outfitted with the Allison transmission were given the Allison shallow transmission drain pan?

Clearence doesn't seem like the gain since the spin-on filter hangs down fairly low.....:confused:

FYI, I do a fair amount of towing and considered installing the "deep" or regular drain pan the next time I change fluid.

Thanks in advance,
Jim M.

P.S. I just realized that this post may be better suited for the "Towing" thread.


COST ! Gm since 2001 has deleted many of the things that make our trucks the nicest on the road. any one notice all the extra lights the gm has removed threw the years? no more glove box light , under hood lights , console lights , visor mirror with lights . it all adds up to cost saving to GM and 99.4% of the new owners dont notice the details.

DmaxMaverick
06-30-2007, 12:04
COST ! Gm since 2001 has deleted many of the things that make our trucks the nicest on the road. any one notice all the extra lights the gm has removed threw the years? no more glove box light , under hood lights , console lights , visor mirror with lights . it all adds up to cost saving to GM and 99.4% of the new owners dont notice the details.
I don't think the shallow pan has anything to do with cost. True, they delete some items and most new owners won't notice, but the tranny pan is still the same size pan than came on the 2001's, when they were first introduced. It about fitment, not cost. The deep pan would be a bad idea for any truck used off road frequently. They do hang below the frame rails, which would be a liability on a rutted/rocky road. I don't have one for this reason.

77TransAm
07-01-2007, 00:06
The shallow pan was actually an extra cost item. The transmissions were designed with the deep pan and filter, and the shallow pan had to be created as an additional design for the GMT800s.

Ground clearance is the issue; GM only wanted to use one pan, whether it was for the lowest 2WD Allison-equipped truck, or the tallest 4WD.

Dakster
07-01-2007, 11:06
COST ! Gm since 2001 has deleted many of the things that make our trucks the nicest on the road. any one notice all the extra lights the gm has removed threw the years? no more glove box light , under hood lights , console lights , visor mirror with lights . it all adds up to cost saving to GM and 99.4% of the new owners dont notice the details.

Don't feel bad, it isn't just GM... All automakers are going it. I noticed it on the Ford's a couple of years ago - The PLUG for the underhood light was there, but the light was gone, Ford even made the "plug-in" diesel engine heater optional.

Lately, prices are going up and amenities are going down.

jsmiracle
07-01-2007, 11:31
Thank you all for the informed responses. I will investigate further before I make the leap to deeper pan. I do tow and I want the transmission to last as long as it can, but it seems as if the deeper pan does not add the capacity as I thought it might.

Take care,
Jim M.

DmaxMaverick
07-01-2007, 12:12
If your goal is to add capacity, it can be done easily, without the deep pan. Adding a sump to the cooling circuit would accomplish this, and effectively "extend" the OEM pan. You could fabricate a tank, or use any of several commercially available hydraulic tanks. I've thought of doing this myself, but never really got the initiative. Maybe now.........

Mark Rinker
07-02-2007, 07:36
I think the capacity of the Allison is more than adequate for most towing duties. If you drag a heavy 5-er across the AZ or CA desert, I stand corrected. Otherwise, your tranny temp gauge will tell you that the fluid capacity is fine - rarely does the temp top 190 in my trucks.

jbplock
07-02-2007, 18:47
I was doing some work on my truck today and snapped a picture of the deep pan relative to the frame...

http://www.thedieselpageforums.com/photopost/data/500/medium/Deep_Pan.JPG

:)

jsmiracle
07-03-2007, 07:26
DMaxMav,
Yes, I was considering adding capacity for cooler temps (longer life) of the transmission.

Mark,
You tow heavy loads much more frequently than I. I rarely see Trans Temps >200F when towing the TT (160F unloaded) in my sig. I don't think I'll be overly concerned.

jbplock,
Thanks for the pic. I didn't even consider asking for one. It's true that "a picture is worth a thousand words".

Thanks, everyone.

Jim M.