Allison Service at 25K?

[mikennola0515]

When I took my truck in at 5K for the spin-on filter replacement, the dealership actually changed both the spinner and the fluid. My question now is, do I really need to replace the tranny fluid at 25K per the maintenance schedule?

Note: The truck is really underutilized (never used for towing, occasionally burdened with 2/3 payload limit for topsoil, firewood, etc.) It is up to the challenge of my daily commute and carrying me and my briefcase:)

Assuming the truck needs the foregoing service, any recommendations as to competent service facilities would be much appreciated (Dayton, OH area) as well as ballpark price #. Have not been real impressed with two dealerships w/whom I've already interacted. Local Allison outpost (Miami Valley International Harvester) does not work on Duramax.

[DmaxMaverick]

It depends on the interpretation of the recommendation. Allison (GM) recommends 50K for "normal" service, and 25K for extreme. By your description, you are on the lighter side of "normal". It didn't hurt to do an early, first service, though.

I would recommend a spin-on filter change at 25K, and a full service at 50K. A full service would be a drain/fill (full flush and fluid replacement would be ideal), and external filter. There is no need to remove the pan for any reason other than repair or overhaul. The internal filter is only to be replaced at overhaul, IAW Allison. The dealer will be more than happy to sell you an internal filter and gasket, but neither are necessary. Old school state of mind, I'd say.

[mikennola0515]

Thanks a bunch for the advice.

[mikennola0515]

DMaxMaverick:

I hit the "Add Reply" button too fast. Is changing the spinner a DIY job? I did not watch them when they did it the first time, but it seems similar to an oil filter. How much fluid would one expect to have to replace for just replacing the spinner?

The drain procedure you describe below seems like an oil change - is this a DIY?

I'm not trying to be penny wise and pound foolish by asking the DIY questions, it's just that I've not been overwhelmed by the professional competence I've seen at 2 local Chevy dealers, and as I said in my first post, the local Allison folks don't work on the light duty stuff.

Yes, I baby this thing (not on purpose, though) - gotta pay it off before I can afford the toys to drag around.

[DmaxMaverick]

Yup. It's all DIY. If you can find your butt with one hand, you can do it.

The tranny pan has a drain plug. A normal drain will yield about 7-8 qts. The filter is just as it looks. Spin it off and replace it. You'll only lose a couple oz. of fluid and it probably won't change the level on the stick. The top of the filter has a magnet that needs special attention. Just don't lose it. Clean it and put it onto the new filter. It's pretty obvious once you get a look.

The full flush is a bit more. DO NOT use a flushing machine to do it (Allison says damage will occur). You pull the cooler return line and let the tranny pump it into a container with the engine idling. Pump, fill, pump, fill.....until the fluid has been exchanged, 17-20 qts. There's more details on this, just search the forum.

It's OK to pinch a few pennies on this stuff. I see no point in paying a dealership $90/hr to do a 2 bit job, and they're slow and sloppy.

[MikeC]

Mike,

I'm getting ready to swap the fluid in mine to either TranSynd (Castrol) or to the Amsoil equivalent. If you want to do yours also, we can get together and do both at once. I can also show you how to change the fuel filter and save some $$$.

you can email me at mcooper at medflight dot com

or call me at 614-302-0885

Mike

[mikennola0515]

DMAXMaverick:

Again, your advice is much appreciated.

MikeC:

We may be a little too far apart to hook up, so don't wait around on me. I do appreciate your offer, however.

This one may be a service I do perform myself as the maintenance budget took a hit last week for $192 to replace the passenger side mirror glass(heated power camper style w/integrated LED turn signal). Really, it was my wife who cracked it backing out of the garage. Ouch.

[dersark]

Hello,
Please give more information on Allison transmission oil change procedure. I called Allison and they said we have to flush it. I try search nothing came up. I would appriciate full information for DIY Allison service.
Thanks.

L. Der sarkissian