Did you replace your transmission fluid filter?

[adic27]

I will be replacing my transmission/hydraulic filter on my 1998 international 3800 which has the dt466e and an Allison AT545 transmission. I looked online some but can't confirm the type of transmission fluid or capacity. From what I read so far I gathered i need an approved fluid, which is a TES 295 approved fluid. How do I determine if school busses are general duty or severe duty? Im guessing it's more of a general use vehicle. Bus has approximately 187,000 miles on it. Im not sure if it ever had a transmission oil and filter change but im sure it's a good ideato changeboth so I'mdoingit. Im going to be using a Wix brand filter. Any advice offered will be appreciated

Thanks

[bigskypc50]

Anyway you can talk to the bus barn your bus came from? They claim you can mix the full syn with the DEX III if your just changing the filter then safe bet would be to use Transynd in case the bus barn used that, that little bit of mix won't hurt anything. If you don't know the service history of the bus look at the fluid if it's anything but burnt and dark brown black, then yes good ideal to drain refill. Someone correct me if I am wrong but in an AT545 since they make so much heat I would use Transynd on your refill.

The duty rating is how you drive it, since it's now a motorhome and will likely be on the highway (they were deigned to be city rigs) I would use the heavy severe duty stuff.

[EastCoastCB]

Dex 3 or tes 295 will be fine. Dex is cheaper TES is better cause its synthetic. They're compatible, fwiw.

The spin on filter isn't part of the transmission but usually there is a spin on filter somewhere near the trans on the frame rail.

[adic27]

Originally Posted by EastCoastCB

The spin on filter isn't part of the transmission but usually there is a spin on filter somewhere near the trans on the frame rail.

Not quite sure what you mean. Are you saying the filter next to the transmission fluid tank has nothing to do with the transmission? It says hydraulic on it. Can't remember the part number. If that's what you are saying could that be a power steering filter? I cross-reference the filters brand number on the wix site and got WIX Transmission Filter 51259 which i purchased on the Walmart website. An O'Reilly's rep told me the wix part number I needed was hydraulic filter 57131. I went with the wix website

Thanks

[bigskypc50]

Follow the cooler lines from your trans, it will be somewhere along those lines.

Originally Posted by adic27

Not quite sure what you mean. Are you saying the filter next to the transmission fluid tank has nothing to do with the transmission? It says hydraulic on it. Can't remember the part number. If that's what you are saying could that be a power steering filter?

Thanks

[Booyah45828]

An at545 will be fine on dex3, unless the district converted it to a tes295, it's not necessary to use a tes295.

The filter will be inline to the cooler.

Like eastcoastcb said, that will likely put it on the frame rail somewhere. Mine is forward of the axle on the passenger side.

[EastCoastCB]

Originally Posted by adic27

Not quite sure what you mean. Are you saying the filter next to the transmission fluid tank has nothing to do with the transmission? It says hydraulic on it. Can't remember the part number. If that's what you are saying could that be a power steering filter? I cross-reference the filters brand number on the wix site and got WIX Transmission Filter 51259 which i purchased on the Walmart website. An O'Reilly's rep told me the wix part number I needed was hydraulic filter 57131. I went with the wix website

Thanks

I'm saying there usually a spin on filter somewhere on the transmission's oil lines. Its usually called "hydraulic oil filter" cause its just a generic filter added by the chassis manufacturer. Mine's a napa I'll get a pic when it warms up a bit outside and there's more sun light.

Not sure if what you're looking at is a power steering or transmission filter. Just trace the lines and see what its connected to.

[cadillackid]

there are 2 filters on the AT545 (sometimes3)..


1. there are 1 or 2 external spin on filters next to the trans.. those are easy to replace with identical ones..


2. there is a filter in the transmission oil pan, the spin on filters are supposed to filter the most dirt.. however the fluid returned to the pan is always first filtered by the pan filter so it can become dirty too.. there are a couple different part numbers for the pan filter.. shallow and deep pan.



if your transmission has the dipstick going into the side of the pan that is the Deep pan (it will be 3-4" deep).. the shallow pan version (earlier transmissions) has the dipstick going into the top of the trans and the pan is only about 2" deep.. you need to buy the right filter for your trans or it either wont fit or wont suck fluid properly..



-Christopher

[Booyah45828]

On allison's we only mess with the internal filter on trans overhaul, or if the fluid was severely neglected. It's more of a screen then a fine micron filter.

There's a few different numbers for them based off the pan and transmission. I want to say napa #1890 (wix # 51890) is the part for the 545 with the deep pan. The number of 545's in the fleet anymore is pretty small, so I might be wrong on that. I can't remember the last time I serviced one TBH.

On the mechanical allisons we'd change the fluid and external filter once a year before the annual inspection and call it good. That's with dex3 in the pan and the bus in route service. If it was a spare, we'd extend that interval out to match the usage. TES295 can take you longer between changes, but we never put the fancy fluid in the old transmissions. The electronic allisons will actually throw a trouble code and a light when they want serviced.

[EastCoastCB]

Originally Posted by Booyah45828

On allison's we only mess with the internal filter on trans overhaul, or if the fluid was severely neglected. It's more of a screen then a fine micron filter.

There's a few different numbers for them based off the pan and transmission. I want to say napa #1890 (wix # 51890) is the part for the 545 with the deep pan. The number of 545's in the fleet anymore is pretty small, so I might be wrong on that. I can't remember the last time I serviced one TBH.

On the mechanical allisons we'd change the fluid and external filter once a year before the annual inspection and call it good. That's with dex3 in the pan and the bus in route service. If it was a spare, we'd extend that interval out to match the usage. TES295 can take you longer between changes, but we never put the fancy fluid in the old transmissions. The electronic allisons will actually throw a trouble code and a light when they want serviced.

After a certain date Allison started shipping all 545's with Transynd.
And all reman 545's came with it. Also- Florida only allows Transynd in buses- its written into the regulations, even.

and correct- there's usually no need to do the internal filter. Only at overhaul is what I've always heard. Unless as you said- some severe duty/neglect.

[Booyah45828]

Originally Posted by EastCoastCB

After a certain date Allison started shipping all 545's with Transynd.
And all reman 545's came with it. Also- Florida only allows Transynd in buses- its written into the regulations, even.

and correct- there's usually no need to do the internal filter. Only at overhaul is what I've always heard. Unless as you said- some severe duty/neglect.

Never knew that.

Is it allison remans your talking about? We used weller for remans and I always thought it was dex3 fluid spec'd and used. With the electric allisons, we've never replaced one/they've all been warrantied and went back to the dealer.

Typically, if one was upgraded to it there would be a tag on the dipstick saying so. We have the tags in the shop.

[EastCoastCB]

Yeah all allison reman 545's came with transynd after a certain date.

[cadillackid]

On my electronic allison I just change the spin on filter once a year and leave the transynd in it. It is still nice and clear almost 4 years later so I won’t mess with it . That transmission is also built for much heavier duty than I even begin to toss at it

I suppose I’ll push it a little harder with my Orion but even still the trans is design for 500 Hp and 1000 tq .. I’ll be looking to push 300hp/650tq at it max.

[adic27]

Originally Posted by EastCoastCB

I'm saying there usually a spin on filter somewhere on the transmission's oil lines. Its usually called "hydraulic oil filter" cause its just a generic filter added by the chassis manufacturer. Mine's a napa I'll get a pic when it warms up a bit outside and there's more sun light.

Not sure if what you're looking at is a power steering or transmission filter. Just trace the lines and see what its connected to.

The spin on filter has 2 lines coming from it and one is going to the top of the transmission. The other line is going to the front of the bus underneath the radiator more on the driver side, maybe connected to it or at least connected to something right under the radiator, can't tell. There's also a third hose (running alongside the filter hose going to the radiator) that it's coming from the transmission to the radiator but on the passenger side of it. The filter is a luber finer part number Lfp1652 if that matters. I cross-referenced it with a Wix 51259 on the Wix site and purchased that for replacement

The white arrow is the hose from the trans to the passenger side of what seems to be the bottom part of radiator and there is another hose in the exact same spot but on the driver side that goes to the luber finer spin on.

Can someone tell me what the red and green arrows are? I was assuming the red is a drain bolt for the coolant? Whats the green arrow?

I wanted to post a link to a vid but my upload spees is capped and reducing for going to the limit. I'll post it when its finished uploading

Thanks!

[turf]

i vote for Dex 3

Dex 6 or Tes295 are to slick for a 545 IMO.

while they say Dex 6 has the same shear strength as the fluid it replaced, there were plenty of problems with backwards compatibility.

without lockup, the 545 relies on the shear strength and viscosity of the fluid in the torque converter to keep you going down the road. i'll take the thicker Dex 3 there.

for a trans with lockup or later than 2005.... i'd probably use the Dex 6 or Tes295.

my 2 cents

[adic27]

Here's a link to the vid showing the spin on

https://streamable.com/e0a2u6

Thanks for all the info so far guys!

[Booyah45828]

Red is the radiator stud/nut that holds the radiator to the frame cross member.

Green is the petcock or radiator drain.

White is one of the cooler lines.

[Booyah45828]

The only issue I've seen was dex6 would eat and ruin the seals in some of the older transmissions. No issue with any of the tes295 options as far as I know.

I've heard john deere hygard hydraulic fluid is a good substitute for the at545, I've never tried it so use it at your own risk.

[turf]

that my opinion!

every other transmission has a mechanical lockup at highway speed. the 545 depends on a fluid lock up of the torque converter. IMO, i want the thickest glue i can run to keep the T/C together and limit slippage.

if you factor in the heat, i still want the thicker stuff in a 545.

yes, the seal issues were on other transmissions, not the 545.

IMO ... clean fluid is more important than slick fluid.....

when i had the 545, i tried both trnsynd and dex 3.

i burnt the transynd off going up mountain grades, replaced with dex3 after adding a cooler.

now i have a locking at1545 and i'm running the dex 6.

i haven't over heated the new trans so i haven't changed the fluid, but i'd be fine with dex3 in the old girl next time.

its 4 gallons with my cooler and tes295 or the dex6 can really add up.

(just a foggy side note..... i seem to recall the military using 30w which would be similar to the hydraulic link i think)

[EastCoastCB]

ts295 is far more resistant to thermal breakdown than dex3.