Do any vendors here sell a remote 48RE tranny filter kit. I hear that the 48REs are dirty transmissions.

 

that's why they want you to flush them every 30k miles

 

i dropped the pan on my 07 after 15k and the magnet was COVERED in fine metal i ran not walked to my trans guys in town rumored to be best in town and they said its normal!!!!! suggested amsoil,deep pan and said a remote filter and cooler would be good [they built my trans for my race car and know i beat up trans's stupid slush boxes break so easy with my driving

 

Remote filters on a stock 48RE are a bad idea, not even a good idea on a built one. Drop the filter and fluid every 25-30k. Given the trans is setup correctly for the way you are using it it should be fine.

 

HUH?! I mounted one pre oil cooler my fluid looks brand new after 20k! I dropped the pan and was surprised to find very little on the magnet!! Why is another filter a bad idea?
BTW I put a magnet on the remote filter Can't wait to cut it open!

 

I find nothing on the magnet and nothing in the pan after 25-30k with no filter. Again, if you have to filter the fluid the filter is not going to address the problem.

Cooler return flow is used for lube and cooling of the transmission. The system is designed around flow not pressure and anything in that circuit that adds restriction will reduce flow. The idea is to maximize flow to reduce trans heat and wear by fixing the NVH shortcomings. Much more effective than adding any filters, or extra capacity.

 

What is the NVH? How many miles do you have on your trans and how hard do you work it? Typically the most junk you will find in the pan on an oil change is at the first change. Did you get yours new?

On my first change there was a lot on the magnet in the pan. As hard as I have ran it this time (Since that change) I will not be surprised to see a lot again. There is going to be wear in there. That is just a simple fact of physics. With movement there is wear. Now if you wear it out or make it fail a lot faster than most everyone else, then you are being too hard on it!! Either buy a tougher one or back off . . . .

You are right about the flow of oil. Oil is any moving parts life 'blood'. Take some away and you greatly shorten it's life. The trans. lines are 1/2" but the fittings are only 3/8" inside. The other thing I noticed when changing my fluid was that there is not much flow or pressure in those lines (at idle). I am convinced that if you install a large enough filter head and filter you will not restrict the flow of oil in there enough to measure the difference (And this is what you want so you don't shorten the life of the trans.). If you have a temp gauge in the line coming out of the trans on it's way up to the cooler, you will know instantly if the trans is getting too hot! Don't ever let them tell you to install the probe in the pan or in a stagnant port on the side of the trans. Those are the last places to heat up and will even be coolest. By the time that indicates a problem, the trans will be damaged!! As a rule, our trans will heat up fast when backing a heavy load. Of course in you are pulling a heavy load forward and can't lock the torque converter they will heat up also. It is always best to get the torque converter to lock up when pulling!!

I plan on installing my own large filter. The kits I have seen for sale use too small of lines, filter and fittings in my estimation. It is not hard at all to source larger items for doing this. Oh, and for me; the reason for installing a remote filter is to catch much more of the particles in the oil than what the OEM filter can. Have you ever seen what is inside the OEM filter. It isn't much of a filter at all! (I have changed lots of filters in other autos that actually only a had screen in there for a filter!) The filter I will use will be around 10 micron. This OEM filter should be able to catch stuff at least as small as bugs (Or what: 150 micron! The junk that will cause wear in there is around 20 micron and larger). . .
Oh, and the oil flow from the trans in the line up to the cooler comes from the torque converter. Any chunks of clutch material that comes out of it goes through the cooler lines and into the trans to lube it. The OEM filter is in the bottom of the pan in the oil pick up before oil goes to the converter. The external filter would prevent junk from moving around in the oil system inside the trans. I talked to the trans expert I know and while he said he doesn't like to see external filters (Because they are usually too small!) he does admit they would be great as long as they are big enough. Well, I can make it big enough to not restrict any oil flow!!! (If you doubt that: look up my new air filter!! . . . LOL) If a guy was worried about restriction he could just install a pressure gauge before the new external filter and it would show instantly if the filter was plugging and restricting oil flow!!

The last thing everyone says is to remove the check ball in the cooler line. It seems like these can fail and plug off the oil flow enough to cause the trans to burn up. So this is another mod that should be done.

 

NVH = noise, vibration and harshness initiatives to make th etrucks more like a car. In the process of making the trans shift like a car its killing it at every shift point because it slips more than it should. Load it down and the situation is aggravated. Address those items and a 90% of the observed problems disappear.

I have 160k on my truck, had since new. Smarty has been on and turned up since about 40k. Burned the direct clutches out of it with too much TQ at 105k. Its used for playing, DD, and 5-15k trailer pulling.

The first change to clean out the junk is normal. These units are not flushed and cleaned before assembled so there always seem to be small filings that end up in the pan after the a bit of driving. The shops I have worked at would rebuild a unit, put about 10 miles in test drive on it then drop the pan and fluid to clean an residual junk and make sure there is not any major issues. The factory doesn't do that so we have to.

Any time you try to filter down to 10 micron the filter is going to add restriction, the feasibility of adding large enough ports and enough surface area to minimize the flow restriction is where things get iffy. Even if you have a 30 psi bypass on the filter you still will negatively affect the flow by the design physics of the fliter and bypass, you can't get away from that. The question becomes how much restriction is too much and that info is hard to come by.

The OE filter is about 40 micron IIRC, adequate to keep larges pieces out of the system but not so much it restricts the ability to draw fluid from the sump, key point as to why the filter is the way it is. Given that the heavier materials will settle to the bottom on the pan and the large stuff won't get thru, its a pretty good system is the trans works as it hsould with minimal slipping and friction degradation. Like I said, if you see evidence you need to filter more the OE will do the filter is not going to address the problem.

Can a better filter help overall life expectancy? Yes it can, but, at what cost by putting it inline?

Consider using a shift kit to boost pressures, add better servos with better sealing capability to stop the slipping on shifts. A shift that happens firmly and quickly will generate little wear particles. The fluid acts as a buffer so frictions and steels meet rotational speeds about the time the the lubricating oil is squeezed from between them. Very few wear particles are generated. The downside to the OE is a firm quick shift that is not as smooth as they like, plus they can't sell rebuilds and parts later either.

Under the stock pressures and typical leaky sealing rings on servos the rotational diffrential is too great to match the frictions and steels as the oil is squeezed. This generates a lot more wear particles and potential grit to run thru the trans.

OE parts on a 48RE are high energy clutches, the stock steels tend to wear faster than say a Kolene steel but thats by design. With the previously mentioned fixes, I have noticed a definite difference in the amount of the black film one sees in a typical stock trans. That film is wear form the steels. When I rebuilt the trans we used new OE clutches and steels, they are wearing much better than they did on the stock system.

Extra filtering is not a bad idea, but, on a stock trans and inline its not something that I believe will increase trans life. Too many other things are more effective. Fix the issues that cause the need for extra filtering and it negates the need for the filter.

 

There is no restriction when plumbed in bypass mode.

Running dirty oil in your transmission is a bad idea.

 

The oem check ball is the worst restriction I've seen! Take that out of the system and add a inline filter and that will still flow more than that check ball ever will!