Transmission fluid and filter change, temperature to check fluid level??

Drainplug_fan · September 12

Good suggestion 64BAwagon. I hope you have better luck with the shape of your pan. Mine had distinct seams and wrinkles where it should have been flat.

I had several of the Dorman and B&M kits on hand when I dropped my pan. I was going to pop one in but I convinced myself that the likely spots without internal interference were not flat enough on the pan. Rather than force the issue, I punted. I would typically put one in back in the TH400 days, but those had more obvious places to work.

If I had my welding gear handy, I would have preferred to weld a bung fitting onto the pan in one of those corner flats. That way, it is not interfering internally, low enough to really drain the whole pan make it worth the trouble, and shouldn't ever be struck unless heaven forbid the whole trans pan is crushed.

redwngr · September 19

On 9/11/2024 at 8:48 AM, Grumpy Bear said:

With the 6L80 at then 192 TBV the check target was above that temperature.

With the 6L80 with the 70C thermostat the target temp was just above that temperature.

Kind of says that the trans just needs to be at operating temperature.

I've run multiple 6.6 Dmaxes with Allisons over the last 20 years. (5 and 6 speed ones, I've not run a 2020+ 10 speed Allison)

Doing 'daily driver' type tasks they have all run much much colder than the GM transmissions.

All needed 'extra measures' to get them up to transmission check temperatures.

Edited September 19 by redwngr

bruceb58 · September 19

Best thing to do is to lower it by the bolts until there is a big enough gap to suction the fluid out. Then...either install a drain plug or buy an aftermarket pan with a drain plug already there.

64BAwagon · September 19

You can tell that Allison wasnt totally involved in the design of the 10 speed by the lack of ease in maintaining it. We had dozens of trucks with Allisons all the way from the old 4 spds to the 1000 series through the 4000 series. Not a one was anywhere near as hard to service as the 10L1000. All had drain plugs and easily serviced filters (most bein spin on) even the cartridge units in the 4000's werent hard to remove.