Transmission Oil/Filter Information - Aristo JZS147 3.0V

[Flashfire118]

Hi

I have a 2002 Lexus GS300SE (JSZ160E) and last week I found red fluid on the floor under the front offside -and found two perished steel pipes going under the radiator which I thought were linked to the steering box cooler but later discovered (as you all probably know) they are the links to the Automatic Transmission cooler rad.

Question if I have been driving for a day or two with very low levels of trans oil in given there was only a small showing on the dipstick when discovered (hot) is there likely to be any damage? the transmission change never batted an eyelid with nothing to tell me there was a problem.

Once the fault was discovered the old pipes were cut out using a small grinder and a number 3 adjuster; (they were absolutely knackered!! what were Toyota thinking of!!) and replaced with braded fuel pipe with a piece of coolant hose to protect it where it went under the radiator (therefore no need to remove all the rad etc.) 6 jubilee clips (cos the spring clips are naff) and a proper engineered solution all around. Unless of course you guys know of a reason why the pipes under the rad need to be steel, but I think it's just a production line thing.

Anyway the next problem I could do with some expert commentary on is...we only had Comma AQF Transmission fluid to hand which is a Dexxon 3 fluid and considered suitable by the assembled gathering (all long serving mechanics and rally cross drivers) as we had let even more fluid out during surgery, and needed to top up, absolute minimum put in (about 1ltr). I then discover from the hand book I needed the Type 4 fluid so went to get some, really difficult locally but I have some on order and won't use the car until it is in...

Question can I just top up or do I need to change the lot as it is contaminated? And are red transmission fluids able to be mixed with impunity?

What is the difference between the comma ASW type IV (Toyota equivalent) and the AQF we used? Is it operating temperature and viscosity and what damage (not scare stories please) could be done if I just fit the type 4 on top of the stuff that's in.

Through out all of this trauma, the car drove at is always has; an F1 car in sheep's clothing (please note I only misbehave responsibly).

Thanks

[jdmvip]

Sorry I missed this, I read the issue you had with the corroded aluminum pipe being quite common for some reason. I think you'll be fine with what you've done, just keep an eye on your fluid level.

Don't use Dexron III, Toyota calls for it's own Type IV fluid and does not call for Dexron III and is not recommended by Toyota or by others (can't remember the reason but there has got to be a good reason I'd think).

I would not mix the different fluids if possible, I'd get the T IV if you haven't already and do a full flush but I don't think the above will cause your transmission to have issues though.

[Flashfire118]

Many Thanks for the response; we took the car through to Goodwood for the revival weekend and it purred there and back no problems with 5 up...so fingers crossed...the reworked pipes are fine and a really cheap and effective repair for what would be a radiator out job to use the correct parts.

Ill I need to source now is a new exhaust (from the cat backwards) and she will be back on song....

[Flashfire118]

I understand there to be just over 8 litres in the auto box so quite pricey when using T4

[98aristo]

Sorry I feel I should chime in here to correct some errors in your flushing guide before more people follow this method and I will explain why. Never drain the transmission pan on any vehicle and then run the engine while empty. What happens is you are running the pump dry and it is sucking up air. This pump uses the oil for lubricating and cooling properties. This is why when you were running your engine nothing was coming out until you stopped it. This was just some fluid from the torque convertor. (Not all of it) next thing to note is that you were pouring fresh fluid in while the plug was open. You are basically just pouring your good fluid down the drain as this does not go through the transmission torque convertor. Just into the pan and out the drain hole. The original guide you posted of using the hose off the radiator was correct assuming you have a transmission cooler. The correct way of flushing when your vehicle has a transmission cooler is as follows. Drain the transmission oil pan. Remove the pan and replace the filter. Reinstall the pan. Pour back in the exact amount of fluid that initially came out when you drained the pan. If 2 liters came out then put 2 liters back in. Now that you have a pan full of fresh fluid, you still have 6 more liters of dirty fluid in the torque convertor which you don't want to mix with the clean fluid you just poured into your pan. To remove this oil what you do is remove the fluid outlet line from your transmission fluid cooler. (Usually at the radiator if you have a water cooled cooler, some vehicles have air cooled cooler that may be installed in front of the radiator.) Now the concept behind removing this line is that after the pump picks up fluid from the pan and sends it through the filter and to the torque convertor it gets used to transfer power and gets hot. Then it's sent to the trans oil cooler to be cooled before it goes back to the pan. Since we are removing the line that takes the dirty fluid back to the transmission we will be able to extract it and not let it return to contaminate our fresh oil. So with the line removed you will attach your own line to the radiator and run it into a container. Now like mentioned in the other guide, have someone start the vehicle and then fluid will start rushing out. Once the amount of fluid that you initially put in comes out (2 liters was the example I used), shut off the engine and put that same amount back in so you don't run the transmission dry. Repeat this last bit until the fluid is coming out of the hose is clean. Reattach the hose and run your car and shift through all the gears on the selector and recheck your oil level. You want it in the cold range and do not overfill. An overfilled transmission is worse than an underfilled transmission. Now drive your car for about 20 mins to warm up the transmission. (Not your engine, it takes your trans longer to warm up than the engine coolant, so don't assume the engine temp gauge has any relation to transmission temp) once warmed up recheck your fluid level. You now want it to be in the hot range. That's it your now flushed! Enjoy!

[jdmvip]

98aristo, this is a bit late but I thought I'd reply and say I agree about the running the engine to try and drain it. This is what I read on some other forums and does not seem to be correct or help. My transmission was fine during all of this but better safe than sorry. I am going to update my OP with a more specific warning to just drain and fill.