Tranny fluid external filter?

[PotvinGuy]

Anyone running an external filter on their tranny? I dropped my pan today. I had put new fluid in about 3 yrs ago. The fluid was still bright red, but there was a thin layer of grey slime on the bottom of the pan. The internal filters are pretty basic and a mess to replace. I was thinking adding an external filter would make it easy and the tranny might last longer. Lotsa tiny passages and valves in the tranny to clog. .

 

[tdkkart]

Check with your local trans rebuilder. In years past many rebuilders sent a fist-sized inline filter out with every re-man'd tranny that had to be installed to maintain warranty.

That said, what you're seeing in the pan is perfectly normal. If you just changed the fluid and filter you're probably good for
another 100,000 miles or so as is.

 

[Gerry]

Yeh That (cant find a smiley)/\/\/\

Dependant on if you are running a rad with the trans cooler built in.

 

[one finger john]

Check Summit or Jegs. I remember a frame mount canister filter adapter that was pretty neat.

Check it out.

John

 

[2old2fast]

In order to pump fluid through an external filter the fluid has to pass through the pickup/filter , the fact that there is sludge in the pan is proof that the internal filter is doing it's job , there's really no reason to have a second filter , the sludge will still be in the pan where it was caught by the oem filter..
dave

 

[fletcherson]

Anyone running an external filter on their tranny? I dropped my pan today. I had put new fluid in about 3 yrs ago. The fluid was still bright red, but there was a thin layer of grey slime on the bottom of the pan. The internal filters are pretty basic and a mess to replace. I was thinking adding an external filter would make it easy and the tranny might last longer. Lotsa tiny passages and valves in the tranny to clog. .

That's not dirt, that's the fibrous remains of the clutch and band material and the clutch plates. It's normal to have a light film. If you see bright metal debris it could be a concern. Dave is right, it's generated by the transmission, so an external filter won't catch it. An external filter will catch debris generated by the pump and converter because it flows out through the cooling lines. I had a converter self destruct and fill the lines with garbage and cost me a rebuild. When I put it back together, I installed an external oil filter that I had on the shelf because I was afraid there could be some ruminants lurking in the external cooler, lines, etc... It was just a remote hydraulic oil filter and it worked good. I changed it and cut it open and found some stuff that made me happy that I installed it. I wouldn't have done it without fearing for trapped debris.

 

[Gerry]

You could well be right but a grey 'sludge' is normally the very fine particles from the converter. Fibrous material is usually black. If the fluid looks like metalic paint when you shine a torch into it you probably have a problem.
As you say the cooler lines need flushing after a trans failure.We use an air line to blow the lines through followed by 2 cans of Cooler Flush and finally another blow with an air line. Seems to work, at least for the last 15 years I have been rebuilding them. We do around 5 transmissions a week and this includes the old favourites from Rods etc.

One we did recently.



Bright metal is a sure sign something wrong as brass debris is.

 

[PotvinGuy]

Thanks guys, I feel good now. The slime was just grey, no metallic at all, and it washed out easily. The TH400 is 20 years old and still going strong. Damn fine tranny.

 

[2old2fast]

The TH400 in my '84 GMC 1ton crew dually has [that's 32 years] 157K miles on it & still works great , w/maintainance they are a great trans.