Any Good Reason to Drop the Tranny Pan

[Petersubaru]

My car, just recently purchased with 45,000mi on it...I did the tranny flush myself useing about 12 qts to do it...the fluid is cheery red and I think very clean...I questioned the subaru mechanic about this procedure and he said that the pan has to be dropped, he could only say that this is part of the procedure...is there something that they do to the tranny that I am not aware of besides also changing out the tranny filter..apparently the drain nut is only there to make it less messy when taking off the pan

[Manarius]

My car, just recently purchased with 45,000mi on it...I did the tranny flush myself useing about 12 qts to do it...the fluid is cheery red and I think very clean...I questioned the subaru mechanic about this procedure and he said that the pan has to be dropped, he could only say that this is part of the procedure...is there something that they do to the tranny that I am not aware of besides also changing out the tranny filter..apparently the drain nut is only there to make it less messy when taking off the pan

You can't get all the fluid out unless you drop the pan....

[OB99W]

My car, just recently purchased with 45,000mi on it...I did the tranny flush myself useing about 12 qts to do it...the fluid is cheery red and I think very clean...[...]

 

If this is in reference to the '01 Outback you've mentioned before, under the conditions mentioned I don't see a reason to drop the pan. The actual ATF filter is an external spin-on on a phase-2 4EAT. Although Subaru says that filter doesn't need to be changed unless damaged, if you didn't put on a new one along with the fluid, at least inspect it; mine developed leakage, apparently from corrosion due to winter road salt.

 

With the fluid flushed and looking good, and assuming the trans is performing well, it would seem that at 45k miles there's probably no reason to go inside.

[Petersubaru]

yes this is in reference to my 01 outback..the tranny plug is not magnetic so the filter needs to be also changed from time to time...

If this is in reference to the '01 Outback you've mentioned before, under the conditions mentioned I don't see a reason to drop the pan. The actual ATF filter is an external spin-on on a phase-2 4EAT. Although Subaru says that filter doesn't need to be changed unless damaged, if you didn't put on a new one along with the fluid, at least inspect it; mine developed leakage, apparently from corrosion due to winter road salt.

 

With the fluid flushed and looking good, and assuming the trans is performing well, it would seem that at 45k miles there's probably no reason to go inside.

[jamal]

It's a good way to get ATF in your hair.

 

I had a fun time replacing the gasket and it still leaks. I'm going to just seal the damn thing with silicone.

 

Anyway it sounds like you gave it a good flush so don't worry too much about it.

[idosubaru]

i would never recommend replacing an internal transmission filter on a 4EAT. first, i've pulled a bunch of them and the screens have never even had a spec of anything on them and they all had over 100,000 miles that i've pulled. before you get all testy with me, realize that it's not even a filter. if it were called a "screen" like it really is, people would be less apt to replace them. your fuel pump also has a screen in it, that noone ever cleans or replaces. no need to debate with me that fuel and ATF are different, i realize this, but my point is that it's not a true filter. so for something at 40,000 it's definitely pointless to replace, particularly with the addition of the screw on filters in 1998. the screw on's i would definitely replace, it's sitting right there so why not.

 

and a previous poster brings up a good point, the transmission pan (and engine oil pan) are tricky. it's not that uncommon for them to leak after being reinstalled.

 

droppping the pan gives you very little. you'd have to disassemble the entire transmission to actually drain it out, that's why they use flushes. the fluid is held in large quantities in the torque converter, valve bodies and other areas where removing the pan can't address.

 

there are two common accepted practices for ATF. either drain and refill multiple times (that's what i do) or have it flushed (either at a shop or rig up a system to do it yourself - i've done that before as well). dropping the pan is not at all necessary unless you had some serious transmission issues and want to check it out.

 

good way to get ATF in your hair....nice!

[porcupine73]

Your '01 should have the 4eat phase II. I'm not sure why the mechanic would say the pan needs to be dropped.

 

The phase II 4eat's have the external filter on the side of the ATF (or in the fender area on the H6's). From the diagrams in the service manual it does appear there is also an internal screen filter but never says anything about replacing it (and it shouldn't need to be replaced if the filter on the AT discharge to cooler catches all the shreddings).

 

The phase I 4eat's have the replaceable screen filter inside; I changed mine and like gary said there wasn't anything on it. But it made me remove a cooler line to get it out and that's when another gallon or so of ATF dripped out.

 

Another way to get more fluid out without removing the pan is to do the 'pump and dump' unhook cooler line method.

[nipper]

My car, just recently purchased with 45,000mi on it...I did the tranny flush myself useing about 12 qts to do it...the fluid is cheery red and I think very clean...I questioned the subaru mechanic about this procedure and he said that the pan has to be dropped, he could only say that this is part of the procedure...is there something that they do to the tranny that I am not aware of besides also changing out the tranny filter..apparently the drain nut is only there to make it less messy when taking off the pan

 

 

There is no good reason to drop the pan. the filter in the pan lasts the life of the car. Its not like the filter in the engine, its just a screen.

Dropping the pan can cause many problems. Once a pan is removed, unless put back on in a specific manner, they tend to leak (they are finiky).

Mechanics like to drop pans becaus e that way they can scare thier customers into other services "look at all the material in the bottom of the pan". The material is normal.

Subaru doesnt even drop the pan.

 

nipper

[nipper]

You can't get all the fluid out unless you drop the pan....

 

You dont have to get it all out, just most of it. Most the fluid is in the torque converter (hence the drain, fill, drive, repeat theory). Also its not as critical in the transmission is 1/10th of a quart, hell if even one quart is left, as the tranny has differnt issues then engine oil.

 

nipper

[Petersubaru]

Thanks guys, I have keep my 86 / 210,000mi working with the drain and fill method with no problems...the fluid still stays very red for a long time ...it shifts with no problem in both cold and hot weather

[jon38iowa]

Where does one find a pan seal for a '99 Forester; I purchased the external filter through Subaru, however they did not repond to my request for a seal. I went to Advance Auto and they were clueless.

Thanks for any pointers.

[idosubaru]

why do you need a pan seal? as the past several posts have suggested, it is pointless to remove it under normal circumstances.

 

if it's to replace the screen (which is not recommended to do and i promise yours will be spotless), the new screen will come with a new pan gasket.

 

otherwise subaru should supply that.

[WoodsWagon]

For other cars, the filter in the tranny is a filter, and it gets clogged over time. In the subaru's the mesh in the tranny is big enough that it won't clog, and the spin on filter on the side does the actual filtering. There's no reason to drop the pan. Do not leave the drain plug out and start the engine to try and drain the torque converter that way. BAD Idea.

[MountainBiker]

Where does one find a pan seal for a '99 Forester; I purchased the external filter through Subaru, however they did not repond to my request for a seal. I went to Advance Auto and they were clueless.

Thanks for any pointers.

My '02 doesn't use a pan gasket, just hi-temp sealant according to Subaru.

[porcupine73]

same here, with the phase II 4eat (external oil filter) the pan gasket appears to be an orange RTV type sealant; no gasket. There is no reason to remove a 4eat phase II AT pan unless you're servicing something inside there such as a solenoid.

[jon38iowa]

why do you need a pan seal? as the past several posts have suggested, it is pointless to remove it under normal circumstances.

 

if it's to replace the screen (which is not recommended to do and i promise yours will be spotless), the new screen will come with a new pan gasket.

 

otherwise subaru should supply that.

Ok here's the deal: I am very anal about my cars(poor care from former owner), and if there is remote possibility of the bottom pan being coated or otherwise dirty then I will clean it! I have to admit,the Transmission is the only flawless working part on this buggy. But again I can not rest until I check it out.

The pan looks to have a seal, but maybe I am wrong. Subaru sent me the internal screen filter by mistake (mine requires spin on) and they did not include any seals.

Thanks for the imput.

[jamal]

Earlier cars had a gasket and then they went to sealant. My transmission was leaking from the gasket, I replaced it, it still leaks, so I'm going with the sealant. Oh, here's what my pan looked like after 170k hard miles:

 

 

I didn't even bother to wipe it off. (the pan is black, that's not grime)

[MountainBiker]

same here, with the phase II 4eat (external oil filter) the pan gasket appears to be an orange RTV type sealant; no gasket. There is no reason to remove a 4eat phase II AT pan unless you're servicing something inside there such as a solenoid.

one other reason: Because you damaged the pan by hitting it on a rock! Don't ask me how I know.

[johnceggleston]

one other reason: Because you damaged the pan by hitting it on a rock! Don't ask me how I know.

 

why did he put rocks in his oil pan.... does that increase gas mileage or reduce oil used??:lol:

[porcupine73]

Yes, I neglected that reason. Please accept my edited post:

There is no reason to remove a 4eat phase II AT pan unless you're servicing something inside there such as a solenoid or because you damaged the pan by hitting it on a rock.

Wait...because you damaged the pan by hitting it on a rock!?!?!

[OB99W]

[...]Wait...because you damaged the pan by hitting it on a rock!?!?!

Note that it was "Mountainbiker" who hit the rock; perhaps there's a connection.