Do I have a deep pan or shallow (Allison 2000)?

TheHubbardBus · 02-25-2020, 01:16 PM

I can post pictures if needed, but if anyone knows what the approximate dimensions are so I can tell the difference, or where I can see images of both so I determine what I've got, I'd appreciate it. Getting ready to service the transmission, including the internal filter, & I'd rather have the parts ready to go so I can get the pan off & on as quickly as possible. I'm guessing I have 'deep' (looks to be about 4" or so), but I have no frame of reference.

Booyah45828 · 02-25-2020, 04:07 PM

If it's a 2000, I'm 90% sure it will have a deep pan. The only allisons that I know of that used the shallow were in the pickup trucks.

Whatcha taking the pan down for anyways? If it's for a service, there should be a drain plug for the fluid and the filter you need to change is the spin on one in front of the pan. The only time you need to service the internal "filter" (more of a screen really) is at overhaul time.

You can change it, but it's just unnecessary.

EastCoastCB · 02-25-2020, 04:56 PM

Pretty sure when I did the fluid change on my old allison 2000 it was the deep pan.

TheHubbardBus · 02-25-2020, 05:25 PM

Quote:

Originally Posted by Booyah45828

If it's a 2000, I'm 90% sure it will have a deep pan. The only allisons that I know of that used the shallow were in the pickup trucks.

Whatcha taking the pan down for anyways? If it's for a service, there should be a drain plug for the fluid and the filter you need to change is the spin on one in front of the pan. The only time you need to service the internal "filter" (more of a screen really) is at overhaul time.

You can change it, but it's just unnecessary.

Honestly, I kind of just wanted to see if there was any visual carnage in the pan. And figured changing the filter would give me a good excuse to do so

On the trip home I had some temperature-related issues that (oddly) got significantly better with each passing day. I'm clueless about this transmission. If I see metal shavings that's easier than trying to diagnose what happened the right way.

banman · 02-25-2020, 05:37 PM

Quote:

Originally Posted by Booyah45828

If it's a 2000, I'm 90% sure it will have a deep pan. The only allisons that I know of that used the shallow were in the pickup trucks.

Whatcha taking the pan down for anyways? If it's for a service, there should be a drain plug for the fluid and the filter you need to change is the spin on one in front of the pan. The only time you need to service the internal "filter" (more of a screen really) is at overhaul time.

You can change it, but it's just unnecessary.

Can you change the spin-on filter w/out draining the transmission oil on the 2000?
(or... 'bout how much fluid will you lose if you're ready, and quick with putting the new spin-on in place?)

EastCoastCB · 02-25-2020, 05:39 PM

There's a spin on filter, a pan filter, and a magnet. If you're finding metal after all that the trans is toast anyhow.

I'd do both filters. Get some Transynd or similar tes295 fluid. If you wana go all out there's a pan filter brace that keeps the filter from ever working its way free in the pan. They're $40-$60.

banman · 02-25-2020, 05:44 PM

Quote:

Originally Posted by TheHubbardBus

Honestly, I kind of just wanted to see if there was any visual carnage in the pan. And figured changing the filter would give me a good excuse to do so

On the trip home I had some temperature-related issues that (oddly) got significantly better with each passing day. I'm clueless about this transmission. If I see metal shavings that's easier than trying to diagnose what happened the right way.

In that case after you change the spin-on filter. carefully cut it open. peel off the filter medium and spread it out over a large shop towel. examine it for sludge. run a clean magnet over the medium and see what you get. then carefully spray brake cleaner or other solvent over the medium to wash the sludge away but leave any non-ferrous bits behind.

Others will put the spread out medium on a clean baking pan filled with solvent to wash everything off the medium. then carefully pour the solvent sludge into a white coffee filter and examine what you got.

Booyah45828 · 02-25-2020, 08:32 PM

Quote:

Originally Posted by banman

Can you change the spin-on filter w/out draining the transmission oil on the 2000?
(or... 'bout how much fluid will you lose if you're ready, and quick with putting the new spin-on in place?)

Yes, if we're taking about the filter mounted forward of the pan that's smaller then the size of your fist, you can swap that out and lose less than a quart in the process, no need to be quick about it.

There should be a circular magnet that is stuck to the top of that filter, clean it off and transfer it to the new filter before installation.

Booyah45828 · 02-25-2020, 08:39 PM

Quote:

Originally Posted by TheHubbardBus

Honestly, I kind of just wanted to see if there was any visual carnage in the pan. And figured changing the filter would give me a good excuse to do so

On the trip home I had some temperature-related issues that (oddly) got significantly better with each passing day. I'm clueless about this transmission. If I see metal shavings that's easier than trying to diagnose what happened the right way.

The inner filter is nothing more then a screen. Change it if you want, but it's kind of a waste of money to do so. Even on the old Allison trannys we rarely dropped the pan unless there were issues.

When we service them, we do it much like you would if you were changing the engine oil. Remove the plug, swap on a new filter, install the plug, add fluid, warm up and check fluid level, adjust if necessary.

I doubt you have any issues, at least none that would cause shavings in the pan. It sounds like the typical gremlins you'd face by running a bus that's sat for a bit.

TheHubbardBus · 02-25-2020, 11:47 PM

I really appreciate all the input, folks. Thanks to each & every one of you

Said it before & I'll say it again, this forum & all of you who populate it is a godsend.

Regarding 'gremlins from sitting a while', does anyone know of specific examples in regards to the tranny that might explain the behavior I experienced (from almost undrivable day 1 to almost no problems at all on day 3)? Could it be something like glazed or burned fluid clogging small passages that get cleared through use? If it works like it did on my last day in I'll be stoked, but it really bugs me to have the problems I had on day 1 without understanding exactly what the cause was.

Booyah45828 · 02-26-2020, 07:35 AM

What did/does the fluid look and smell like?

Was it shifting funny, not going into lockup, slipping under load, or anything else you noticed?

Or was it just running hot? and how hot was it running?

If it was a mechanical issue, like burned clutches, slippage, or something broken, you'd still have issues. The fact that you don't leads me to believe it was something in the cooling system related. Maybe the radiator was full of dust and dirt and need driven hard to blow it all out. Maybe a good radiator cleaning is what you need?

banman · 02-26-2020, 08:26 AM

I speak from no deep experience with buses but I'll conjecture --

If the tranny sat a long time it's possible some of the seals and pistons in the valve bodies swelled, shrank, got 'gummy' and now that you've "exercised" them a bit, they're back to moving freely, and/or sealing correctly.

The A2000 is electronically controlled --
My bus had been sitting for a while -- almost every electrical lead I've touched on it has some level of corrosion...
If the electrical input/outputs are far enough off -- these signals will give "bad" information to the transmission; which it uses to shift.

The more you drive, the more the wiring gets vibrated and the signals come back to spec...

When you get a chance you can have the trouble codes read from the transmission. That might give you a clue.

ChuckRatto · 03-07-2020, 04:47 PM

Like the others have said, Im also pretty sure you have the DEEP PAN. As far as the internal filter changing, maybe wait and see what you drain out first. If the bus has been in a fleet service program you might not need to drop pan. Decide when you drain the fluid.

marco polo · 03-07-2020, 05:34 PM

I'm in the midst of replace an Allison 545 with an Allison 2000, I've been trying to learn about them so here's my shot at what might be the problem with your Allison and how it got better. The computer on the Allsion learns your driving habits to set shifts- I think, perhaps your TCM was reset, flashed or lost it's memory? This could explain how it got better over time as the transmission "learned" Just a guess from a guy thats learning

Seriousracer · 03-09-2020, 03:06 PM

Run the transmission serial number through myallison.com. It will tell you what you have.

TheHubbardBus · 03-10-2020, 04:36 PM

Thanks guys.

Was going to detail how the transmission was acting when picked up but to be honest I don't remember all the details, so it might do more harm than good trying to figure things out from missing or inaccurate data. Just took Mr. Beefy to get new shoes and zero problems. I'm going to go ahead & service the transmission w/ just new fluid (transynd) & spin-on filter & leave the internal filter alone. Will also go through cooling system as well.

On our first long trip out of here I'll be better prepared to detail any problems we may have. Hopefully there won't be any

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