Anyone actually seen the factory A/T filter?

Lumpy · Jan 30, 2009, 01:15 PM

My 2003 Lancer is almost at 120,000 miles, so I'm considering changing the trans filter. For the longest time it has what feels like hard downshifts when it's first running. The street I live on has a back way to leave that is safer (no blind curve) that I usually use, which involves stopping at three corners for stop signs before leaving the neighborhood. At the first two stop signs slowing down, it feels like the transmission thuds, shaking the body a little.

This has been going on for a while now and doesn't seem to be getting worse. However, with the mileage it has on it, and the fact that in a couple of years I would like to be buying a new car rather than a new transmission, I'm wanting to change the filter. It's already been flushed at around 60,000 miles and I'm worried that flushing it again won't be enough.

Has anyone on here actually seen a factory Mitsubishi automatic trans filter for these cars? I've non-mitsu service manuals at a PepBoys that showed the little canister type, but my searching on here says that is incorrect. I called them up recently and had them pull the part from the shelf and it supposedly wasn't a canister or the traditional pan type but something else different. I haven't gone to see it yet, because for all I know, it's wrong too. So, before I have to go all the way to St. Petersburg to the only dealer around here (stupid Tampa Mitsu closed AGAIN!?!) to look at this filter, I'm wondering if anyone on here has actually seen or changed it.

I don't have to tell you that the economy is not good right now, so I'm also wanting to do this in my driveway on a weekend. I know with a couple hundred dollars, I could just have a transmission shop replace it, but I don't really have that to spend right now. I already spent over $100 on a case of Mitsu trans fluid over a year ago, and I know Crypto wrote a good how-to on a trans flush, so I might as well use it. I just don't want to end up eating the cost of a transmission in a year or two when I should be shopping for RWD goodness. Is this majorly complex, or is it just a matter of dropping the pan, changing the filter and gasket, and then having the pan bolt torque specs to tighten it up?

Any help would be appreciated.

Edit:
-It should also be noted that this car is equiped with solid engine mounts. Could this thud have always existed and the solid mounts just made it more noticeable?
-At the 60,000 mile flush, it was not flushed with the Mitsu trans fluid. It was just the store brand stuff that Pepboys was using. I think it was made by Gumout, if I remember correctly. Could this just be a fluid problem? Or could this fluid be a bit inferior to the Mitsu fluid, maybe getting to the end of the fluid's useable life-cycle prematurely?

mcgarvey · Jan 30, 2009, 04:19 PM

The filter is not really a filter in the traditional sense of the term, it is simply a very fine screen. There's not really any reason to change it. Simply drain and fill your ATF at regular intervals. If you're concerned, you may add an inline filter to the cooler line. Mitsubishi automatics are generally pretty reliable and if serviced regularly should last 150,000 miles or beyond.

Lumpy · Jan 31, 2009, 03:01 AM

Okay, I think I read someone on the Evo side of the site tell someone that recently. But if that's the case, then why do companies such as Purolator or Beck Arnley make supposed filter kits for this car if it's not a changeable filter? I'm not trying to be a jerk, I'm just wondering if you've actually seen this or if this is something you're repeating that you heard from someone.

mcgarvey · Jan 31, 2009, 02:52 PM

Yes I've seen it first hand. And not just once or twice. It's just a mesh screen, not a filter that's designed to be serviced. You CAN change it by dropping the pan, it sits below the valve body like most filters, but the factory one does not need to be changed, as it doesn't really collect any debris. It simply prevents particles from being taken in through the pickup. They simply fall back into the pan. I've taken trans pans down after 200k miles on F4A4Bs and the filter mesh has nothing on it.

Bottom line: unless the pan gasket is leaking, don't worry about it!

Drain and fill regularly, like every 30k is good, and use the Mitsu Diamond SPIII fluid.

Installing an auxiliary cooler will also help out big time!

---Former Mitsu Master Tech
Current Toyota Master Tech
ASE A1-A8/ L1

Lumpy · Jan 31, 2009, 11:43 PM

Thank you, this sounds like good and credible advice. I just wanted to get something definite since I've read so many threads about what is usually in the pan and what people think might be in there. I really appreciate the help.

Jehuty · Feb 1, 2009, 07:50 PM

Yeah changing it is pretty pointless, and it's more hassle then what it's worth. Where do you get an auxillary cooler? I wouldn't mind to get one either, is it something that helps with manual trannies too?

Lumpy · Feb 2, 2009, 08:41 AM

Pepboys used to (and probably still does) sell Hayden trans coolers in various sizes. I'm not sure about the manual trans question though because I haven't owned a manual car in a long time. I remember that a lot of muscle car guys used to buy trans coolers. But that's still not a definite manual car.

mcgarvey · Feb 2, 2009, 08:57 AM

I reccommend the Hayden #404 inline cooler. Mount it just in front of the A/C condensor.

Jehuty · Feb 2, 2009, 09:44 AM

Quote:

Originally Posted by mcgarvey

I reccommend the Hayden #404 inline cooler. Mount it just in front of the A/C condensor.

It works with either type tranny?

ThunderOZ · Feb 16, 2009, 04:38 PM

So I've been thinking about the tranny cooler but I'm at 146,xxx miles right now and have never done a transmission flush. Someone told me that if I do it now, it will cause the tranny to slip, b/c the gunk in it is actually holding it together. It still shifts pretty well, even with the turbo on the car now

Can anyone shed some light on this for me?

4g94T · Feb 16, 2009, 05:04 PM

Quote:

Originally Posted by ThunderOZ

So I've been thinking about the tranny cooler but I'm at 146,xxx miles right now and have never done a transmission flush. Someone told me that if I do it now, it will cause the tranny to slip, b/c the gunk in it is actually holding it together. It still shifts pretty well, even with the turbo on the car now

Can anyone shed some light on this for me?

yes thats what a mitsubishi technician told me also.it is critical to change it at 30k

mcgarvey · Feb 17, 2009, 07:26 AM

That's a big load of BS about leaving it alone at that mileage. While flushing would not be a good idea (it never is, at ANY mileage), a drain and fill never hurts. Go ahead and do it-- the damage from not maintaining your car is already done but you can prevent further damage.

Why can't people just change their fluid on time?

ThunderOZ · Feb 17, 2009, 12:09 PM

Quote:

Originally Posted by mcgarvey

That's a big load of BS about leaving it alone at that mileage. While flushing would not be a good idea (it never is, at ANY mileage), a drain and fill never hurts. Go ahead and do it-- the damage from not maintaining your car is already done but you can prevent further damage.

Why can't people just change their fluid on time?

I guess I'll just do a drain and fill then.
The tranny has taken a beating and preformed fantastically this entire time so I wasn't in a rush to do it. I plan on doing a manual swap later down the road, but I want to car to run well up to that point.