Transmission Filter

[lenore]

well I did it, installed the transmission filter (Perma Cool). Made a bracket to lift the mount for the filter 3/4 inch from the left frame next to the radiator and under the battery. Looks neat, took existing transmission line off tranny and hooked to the output of the filter and made a new line from the tranny to input of the filter.

The filter is same size as a PH8 ford filter (quite large) and spins on. Filled the filter full of TYpe IV and tested car, works great and no leaks. Now my 99 Lexus RX has a real filter that can be changed by spinning a filter on and also provides additional fluid to the total. Next a cooling fan to the aux tranny cooler. Maybe to be switched on during heavy commute traffic and high outside temps. Will keep everybody posted. By the way the filter assembly ended up costing about $35 but the filters are cheap at any auto parts store.

[RX in NC]

Let's hope this solves your particular problem. Keep us posted with your opinions on whether or not you believe that your new external filter is making a difference in your transmission operation and lifespan. Have you decided how often you'll change the T-IV fluid now?

[lenore]

I will continue on a 15k change cycle. before my tranny failed I was on a 30k change cycle.

[douglasmiami]

I just happened to look at your post and I was interested in what you were doing with the external filter and the transmission cooling device. I too have the '99 RX 300 and am concerned about all of the transmission issues with this year / model. Can you explain briefly what your original concerns were with the filter and the cooling device? What led you to do all of this? I read another post recently that talked about a cooling device, but it didn't make sense to me because my hesitation problems with the transmission occur when the tranny is cold (first drive in the morning). After the car warms up, I have no tranny issues.

Thanks.

[TunedRX300]

Check out SKperformance's thread on Tranny Filter

[lenore]

The filter I installed is quite different from SK's thread, it is just basically a large filter similer to an oil filter, hopefully to eliminate any small debris and metal from staying in suspension in the tranny fluid. I believe SK's was some sort of Magnetic in line filter which probably is great also. My wife commutes a very heavy back street in sometimes 102 degrees and up in the summer. The fluid in the RX300 AWD seems to turn very black and burnt smelling. I am going to add an aux cooling fan to the aux cooler infront of the right wheel well. Probably going to make it a manual switch for summer time use and try to keep the tranny fluid as cool as possible. The cold morning shifts are indeed normal, since the day I bought the vehicle in November of 98. The filter I added is quite large and will actually add fluid capacity. It is the size of a PH8 Ford filter... doing anything I can to enhance my third transmission. I will also continue to change fluid every 15k miles.

My original concerns were brought on by two transmission failures and burnt fluid/very black everytime I had changed it (every 30k until the first failure). Note that the burn't and black indications are evident with everybody that has had the fluid changed. For those that the dealership did this you would not know because the mechanics probably don't tell you.

[lenore]

Just wanted to update on the filter installation. So far everything is going well, the transmission is shifting as normal and their are no leaks. I bought some more Type IV and will change the fluid in the future.

[SKperformance]

If i am correct the filter you installed is rather large.

WHile having a larger surface to catch debris is great it also requires more pressure to be able to pass the fluid inside the canister assembly and back up through it to get out again.

I am not sure if you are doing any good or causing more wear from the posibilities of oil starvation .The tranny pump is very low pressure in the range of 20-50 psi compared to an engine oil pump which those filters are designed for which vary from 20-100psi easily.

I know the type of filters and as much as i wanted one i would not reccomend anything that elaborate because of its design.

[lenore]

I placed filter in a vertical position and filled it with tranny fluid, If it is full all the time would'nt the pressure remain the same, also A tranny site says most transmissions push about 60-90 lbs of pressure. You got me thinking, but I am not to sure about fluid starvation. As long as the system doesn't trap air seems to me it should be fine. any other thoughts? Perma cool hopefully is marketing this properly. They said it is definetly a tranny filter system and put in series to the coolers directly from the tranny output. The oil is filtered prior to going to the transmission cooling.

[SKperformance]

Tranny pressures will be much higher inside the trannyto apply the clutches and gears but not going through the cooler.

It being full or not is not where the pressure changes but with the added chambers and direction changes it will slow the pressures as it is made to just push fluid through a straight line. That is why a choose a simple filter that doesn't deviate the original systems pressure.

If pressure was that high outside a tranny there would actually be a tranny pressure gauge. No one makes one except for a temp gauge which i have already asi already tried to get one but the pressures would not show up on them.

[lenore]

I contacted Perma Cool to discuss what SK said about pressure losses. They assured me that because it is a free flow filter that no pressure changes occur in the fluid to the transmission.

[dcfish]

I contacted Perma Cool to discuss what SK said about pressure losses.  They assured me that because it is a free flow filter that no pressure changes occur in the fluid to the transmission.

←

lenore, I have been following this thread and I beleive that there would be no loss of pressure in the system , If there was any pressure loss it would be +/- a pound or two at best which I'm sure is well within factory specs. Low pressure systems have a lot of tolerence leway.

[lenore]

Thank you for following this thread, I was getting nervous after what SK said about pressures, but you and Perma Cool both feel no problem. I would'nt think they would market the product if it caused problems

[dcfish]

Thank you for following this thread, I was getting nervous after what SK said about pressures, but you and Perma Cool both feel no problem.  I would'nt think they would market the product if it caused problems

←

I think automobile mfg's should have easily accesable removable filters on all of the fluids. Unfortunatley this will probably never happen. You should have no problem with your nice new filter and you did the right thing. GOOD FOR YOU

[SKperformance]

I guess the only way to know for sure is to add a pressure gauge to the ends.

This is yours right?

This is mine

My feeling is this type system is made for trucks or larger vehicles which use more pressure though a external cooler ,rad heater/cooler then through the filter .

Since the small one does not change direction of the flowing pressures it is not adding turbulance by redirecting the flow. Same principles in driving tires like to go in one direction. The second you start turning they slow down .

just like the fluid will.

I guess the only way to know for sure is to add an oil pressure gauge with the filter kit and without it.to see the exact pressure drops.

After checking my Lexus service manuals it only shows the load of internal pressure for applying clutches and gears which is 50 at idle and 160 at stall speed.

Does not apply to the tranny lines as the little hoses held with a spring clamps would blow off with more than 50psi that is used on the cooler lines.

[lenore]

Yes that is the kit I installed, without the temp guage. Would be nice to put that on the oil filter for the engine, which can be a challenge to get to on the RX300.

[SKperformance]

There are kits to relocate the engine filter from many companies to make it real easy to change.

[lenore]

Yes I know, but where could you locate it on the RX300, There isn't much room left under the hood with a neat hose routing.

[SKperformance]

I would put it behind the bumper in the left or right corner which has some room in there.

[cardona6569]

If i am correct the filter you installed is rather large.

WHile having a larger surface to catch debris is great it also requires more pressure to be able to pass the fluid inside the canister assembly and back up through it to get out again.

I am not sure if you are doing any good or causing more wear from the posibilities of oil starvation .The tranny pump is very low pressure in the range of 20-50 psi compared to an engine oil pump which those filters are designed for which vary from  20-100psi easily.

I know the type of filters and as much as i wanted one i would not reccomend anything that elaborate because of its design.

←

Hello: I have to disagree with your post, many cars just run 40 psi in the engine pumps, unless is a variable pump on sporty types. I do not think it is causing any harm to the tranny, in any case is just making it last longer. I would also recommend for the people whose tranny slips in the cold etc. to use a product called Trans X, even as I recommend Lucas, this is far better for slipping and hesitant transmissions. If it does not get fixed with that you need mechanical repairs. 15k fluid change is great, you can add Slick 50 tranny additive or tow kool tranny additive to combat the high temperature issues, besides the cooler you installed.

If in this forum there are engineers please opine on this subject.

C. PR

[SKperformance]

Engine pumps and tranny pumps are 2 different animals completely.

An engine pump is more variable in pressures while a tranny one is more consistent.

Slick 50 is a well know scam and has been fined for causing more damage than anything so you might need to reevaluate your usage with it.

All of those tranny fix fluids do is expanding seals and clutches only a band aid not a solution.

Like i said the only way to know is to install a pressure gauge before and after the filter to know for sure .

I am no engineer but i custom make all sorts of parts.

I designed this fix to combat the problem by finding out exactly what the failure was which is not a complete transmission rebuild but to remove the filter media which clogs the valve body.This is all from the TC shredding the fibre backing on the plates which cushion the metal on metal rubbing.By removing this fibre you keep it from doing one of 2 things .You keep it from clogging the screen mesh and the valve body.

By basic physics anytime you change the direction of anything you will lose velocity of what ever it is you are moving.

So it is not a question of "if" there is a pressure drop but by how much the drop is.The cooler lines are external and do not get direct pump pressures.this makes the fluid pressure much lower than inside the tranny.

So in order to find the problem and find a solution it came from reverse engineering the effects.

To solve it

1. Never keep the tranny in O/D when you know you are going to downshift .

2. install an external tranny filter to catch the fibres which the screen cannot.

[cardona6569]

Engine pumps and tranny pumps are 2 different animals completely.

An engine pump is more variable in pressures while a tranny one is more consistent.

Slick 50 is a well know scam and has been fined for causing more damage than anything so you might need to reevaluate your usage with it.

All of those tranny fix fluids do is expanding seals and clutches only a band aid not a solution.

Like i said the only way to know is to install a pressure gauge before and after the filter to know for sure .

I am no engineer but i custom make all sorts of parts.

I designed this fix to combat the problem by finding out exactly what the failure was which is not a complete transmission rebuild but to remove the filter media which clogs the valve body.This is all from the TC shredding the fibre backing on the plates which cushion the metal on metal rubbing.By removing this fibre you keep it from doing one of 2 things .You keep it from clogging the screen mesh and the valve body.

By basic physics anytime you change the direction of anything you will lose velocity  of what ever it is you are moving.

So it is not a question of "if" there is a pressure drop but by how much the drop is.The cooler lines are external and do not get direct pump pressures.this makes the fluid pressure much lower than inside the tranny.

So in order to find the problem and find a solution it came from reverse engineering the effects.

To solve it

1. Never keep the tranny in O/D when you know you are going to downshift .

2. install an external tranny filter to catch the fibres which the screen cannot.

←

Hello: I was a Jet mechanic for about 10 years. I know that a pump is a pump, their design may be a little different depending on the aplication, but they both produce the same absolute PSI (in the pure sense of the word, like an oil refinery refines oil), even as the pressures vary due to design aplication. But with the info from your manuals the pressures are within range of both pumps. Yes checking it with a gauge is the best. But I believe the system installed is doing no damage, if it was intefering with the tranny he would have noticed problems, like not getting into gear due to lack of fluid pressure, which he has reported in the negative with the info we have.

About Slick 50, I think is a good product have used for years, but only if the transmission does not slip. I only suggested it as a buffer to repel and improve the fluid. Towkool on the other hand lowers the temperature of the fluid up to 78 degres I believe, it is also a good alternative to keep the fluids from failing. Because the burnt fluid is due to mostly two factors, high temperature caused by the outside and the load to which the engine and transmission are subjected to, and clogging of the filter, the two common factors, no fluid lubrication =burned fluid. Another cause is the internal rubing of the parts to which the fluid should be a buffer against, the cooler sliker the fluid the best counter messure against this natural metal to metal rubbing, this is what the before mentioned fluids try to buffer.

I believe the fellow owner with the new design improvement can possible rest a little more assured now. Changing the fluid of a problematic tranny car at 15k is a great policy. I had a warranty by Ford on the Cougar that said that for it to be valid I had to change filter and tranny fluid every 25,000 miles. That tells all of us that in some vehicles going 30,000 miles without changing at least the fluid before is not a good policy. Change the fluid alone and check condition in the middle of the cycle, considering that a Lex is an expensive investment expending the extra bucks is not a bad thing. Considering also that it has a drain plug unlike most american cars that in order to change the fluid partially, you have to take the pan off or become skilled at removing the radiator hose, which is a lot worst than taking a simple plug and improve the fluid.

My experience with trannys is the following:

I have had 8 cars, I have rebuilt two trannys, one because the car was pretty old and came with problems to me from the moment I bought it Oldsmobile cutlass, used five years with tranny from the engine I changed never rebuilit, the one that failed was the original which was discarded with the new engine my uncle used for five more never rebuilt it either, used slick 50 every year, the second because of bad practices of the dealer, because all it had was a bad torque converter but the dealer went ahead and rebuilt it, Honda Prelude 1993, 37,000 failure slick 50 here also, when it was I traded it had about 105,000. Then the other six cars I had and have, one a Diamante had over 220,000 in his tranny slick 50 trans x , never rebuilt it, Mercury Cougar 1987 10 years usage( Slick 50), broke after ten years had overdrive problem with 135,000 miles on it, and the car had been recked and stayed a logn time in the shop which caused the situation, Nissan Murano, CVT have it since new, Pontiac Grand Prix corrected leakage from previous owner 133,000 miles no problems here and running strong, Lexus with 74,500 miles only have it for couple of months do not have any problems.

To the Lex I will change it at 30,000 miles intervals the filter & fluid, the fluid alone I probably change every 15,000 like I used to do the Diamante. I also had an 85 Cougar, great car never changed fluid on the tranny because I traded it in for the 87 Cougar in less than the 30,000 thousend miles and it was my first car and did not have the wealth of experience with trannys I have now. ON the 85 I was waiting the 30,000 miles cycle.

These are only guidelines, but I think they are sound. The thing is that you change your fluid regularly. Draining it from the plug is not a complete change but an improvement of the fluid but since you are doing it every 15k it is order to keep a fresh flow of fluid in the tranny.

C. PR

[SKperformance]

All of your post is great ( especially the slick 50 part)but how does it show factually that the pressure changes are of no conciquence>?

[MichiganRX300]

I have run full synthetic ATF in 99 RX300, and now have over 260,000 on original equipment. No problems due to heat etc.etc. Changed fluid apx. 50-70,000 miles and never had a burned or black color/smell. Additionally have run nothing but full synthetic in the differentials.

[lenore]

Is your RX All wheel drive or front drive only? And what kind of synthetic have you ran in your Lexus?