vinster29

Hey guys,

I'm thinking about getting a factory transmission cooler installed on my 99 RX300 and I was wondering what model years did Lexus begin installing transmission coolers on their RX300's? I am also planning on getting transmission flush done and I was wondering if I should get a full transmission flush done or a drain and fill done since it is the first time I will be getting a transmission flush done on my RX? Currently my transmission fluid is bright red. Any info on this would be helpful. Thanks

Lexmex

If you have an AWD, you should have one. My 99 has it.

Unless you have some silvery pinkish fluid (which indicates material/metal in it), I don't advise getting a flush. Drain and fills do just fine.

vinster29

Thanks for your reply Lexmex,

I was wondering do you have a factory or aftermarket transmission cooler? I have a FWD RX300 but I still think that it would be a good idea to get one. How much do transmission coolers usually cost to get installed by a local mechanic? Again thanks for your help. The pic is great!! Do you have any more of the transmission cooler?

Lexmex

It is from the factory.

This is one from the front passenger side wheel well where the vent is (I guess I could take more if there was a certain angle you wanted to see).

The coolers themselves can range in price from $30 USD to above $100 USD depending on quality. I wouldn't know offhand how much one might charge for it.

salimshah

We have seen posts regarding tranmission issues and that seems to have spooked folks. This has lead to a possibly wrong conclusion that transmission fluid needs to be replaced/flushed more frequently. I can not make the claim that this is wrong, but I am of the feeling that it is some what unnecessary.

Unlike engine oil, the transmission oil is not exposed to burnt gas. It simply lubricates as well as provides viscous coupling. Along the way it does pick up worn off pieces. These pieces will either remain suspened or become sediments. The filter screen traps some of it.

The decomposing if any happens trough temprature and time. If you think your transmission is stressed by extra load (tow or moslty laden cab) or going through mountainous terrain, get the extra cooler and replace the fluid more frequently.

The drain an fill get rid of the sediments and also % removal of suspened particles and aged fluid. The flush would get most of the old fluid out, with the potential of distributing the sediments all over (depends on how the flush is being done) is there.

If you go to the extreme of changing fluid daily, I doubt that would ensure you will not have trasnmission problem. This makes me think that the flush is not getting you any additional gaurantee over drain and fill.

Then there is a dreaded overhaul question at certain milage. 150k miles, 200k miles, 250k miles (choose the one you like). At that milage the tansmission needs full clean up and one can address changing the screen filter and the magnets + crud at the bottom of the pan.

Salim

Lexmex

This is what I found about a year ago when I did a drain and fill and note the accumulation on the magnets.

TunedRX300

ATF is a hydrolic fluid, a coolant, and a lubricant. The base oil of engine oil and ATF is clear and colorless, cherry dye is added to the ATF for leak detection. Color of the ATF is not an accurate indicator of the physical and chemical properties of the ATF. How can one tell the PH balance and how many PPM of wear metal by eyeball-ing the color?
I prefere non-invastive technique such as disconnecting the tranny cooler in addition to draining old ATF via drain plug will get 70% of old ATF out.
Transmission is a closed system, metal particles must be drained off with ATF, the more % of ATF you replace, the longer the overall ATF will last.

thomas1

I am on two sites (Lexus) and the failure rate on the AWD is very high for a vehicle of this breed (toyota), I have experienced the complete failure and I am presently on number 3 tranny. The 99 and 2000 RX AWD has a design problem on their tranny, and the frequent fluid changes at least remove the debris and burnt fluid which has been destroyed of its proper lubricating properties. I continue to get email failures which I have been tracking. Lexus refuses to stand behind their product on this car and lies when it comes to what the maintenance should be. I personally would use 15k miles intervals on the RX300. If you live in a hot climate and do a lot of bumper to bumper commutes than it is a necessity. good luck

salimshah

thomas1:

Did you follow your own advice of 15k transfluid change on 2nd transmission?

Do you have any information as to what component failed inside transmission?

Assuming every one who had tranmission failure contacted you, what is the % failure rate?

Salim

HarrierAWD

According to Consumer Reports owner survey, the RX300 tranny has the highest reliability rating (less than 2% owners with issues) across all model years. Local traffic condition and driving style can indeed affect tranny reliability.

Monitor the tranny fluid level and color monthly. It should be cherry red in color in optimal condition. The red dye fades as the ATF experiences high temperature, so it's a good indicator on the ATF's condition. Have a drain-n-fill done when you notice the ATF fades. Flush should be done only in extreme circumstances, such as when the mechanic put in the wrong ATF.

TunedRX300

I will let OEMs statements speak for themselves about relationship between ATF color/smell and effectiveness.

From Honda, see boxed texts:


From Chrysler reported at http://theoildrop.server101.com/foru...Number=519572:

toy4two

the factory tow package included a tranny cooler.

thomas1

When mine failed I had changed the fluid three times (every 30k) with filter.
This was at 98k miles. I was on vacation two states away when it failed.
the second tranny was defective from the start and it took me two months to convince Lexus of Roseville to fix it. I have since added an external tranny filter and am planning on a cooling fan for the aux cooler. The stupid aux cooler is buried inside the wheel well with the air path blocked by the windshield fluid resevoir and very small louvers in the wheel well. Not a very efficienct method of cooling the tranny fluid. But that was what the 99 RX came with on the tow package vehicle. I do not tow by the way. I have taken meticulous care of the vehicle, but will admit that the commute is down city streets everyday, so no real highway driving during work. Bad design and if you go on the other lexus site there are som folkes very knowledgeable about the changes from the 99/2000 to the 2001. and in 2004 they got rid of the method of shifting completely. Lexus has a design fault and will not pony up to the plate like hONDA /aCCURA DID. bY THE WAY YESTERDAY A Dealership on the east coast admitted a design problem and a 1 in 400 failure rate. Percentage wise not bad, but the admission of a design flaw is significant. so beware and continue to file complaints with the NHtS board online if you have a failure.

salimshah

Thank you thomas1 for sharing your experience. Unfortunately, nothing is helping in getting to the bottom of the problem.

Is the problem related to transfluid, shift point or failing comonent in the transmission. Auto trans is the most complex piece. The motor is magnitude simpler in complexity and parts. Lexus is not sharing what is failing even if the failure rate is low.

But I am digressing .... to return to topic of this thread .

Is the failure of trans is due to poor maintenance (not following manufacturers reccomended service)?

Is the manufactureres reccomended service interval too long. causing failure? [Key word being causing failure. For this the fluid has to be the reason of failure .... like engine oil for oil gelling (that is what Lexus claims for oil gel issue).



Salim

skippy911

I changed my oil the other day and *gasp* my tranny fluid is black. I have a friend who will do the flush for me at his shop but he doesn't have the atf 4 fluid. How many quarts will I need to buy to do the entire flush and fill? Thanks Oh btw, toyota wanted to charge 189.99 to do a flush! Is it just me or is that not ridiculous??