transmission fluid change (1 Viewer)

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I'll add. IIRC your rig has been flushed before. I'd just do a full flush than. Unless fluid smells burnt. But even then I get to a full flush after just a few dain & fills. You go off road so much with that beast. If trans going to fail, find out now. But I'm 90% sure, a full flush is not going to reveal a weakness.

BTW are you monitoring your ECT (engine coolant temps)? If so what are you seeing?
Thanks for the detailed reply. Your info is always the best. I am pretty sure that I would trust you over Toyota now! :clap:

The color of my trans fluid still looks really good. This is pretty impressive given that my truck tips the scale somewhere north of 7000 lbs and most all of my driving is in the mountains going up and down in elevation. I just want to make sure to keep up with the maintenance so that I can make it to 500k. I 100% agree with what you are saying about a normal flush not being an issue. We have also discussed avoiding power flushes which like the plague.

I also agree that if a part is close to failure, I would prefer to have it go where it is hopefully easy to fix. Or in the event of the transmission, close to your shop!

Coolant I have seen a range in temps of between 173 to as high as 198. The average is right around high 170s to low 180s when moving. The 198 was when I was moving slowly on trails in Moab and it was full sun and about 95 degrees. Even that was only for a moment before it came back down to the mid 180s.

Trans temps seem to be between 135 to 165 in normal highway usage. When going over mountain passes or climbing off road I need to lock it in a lower gear to keep trans temps in check. Without locking the gear, trans got up to about 215 when going over Monarch Pass. That is the highest I have ever seen the temp go. I usually maintain higher trans temps off road because of all of the climbing. I now make sure that trans temps never go above 190. If they start getting into the upper 180s, I will usually switch over to low range. This will cause the temps to drop quickly back into the 150s usually.
 
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Thanks for the detailed reply. Your info is always the best. I am pretty sure that I would trust you over Toyota now! :clap:

The color of my trans fluid still looks really good. This is pretty impressive given that my truck tips the scale somewhere north of 7000 lbs and most all of my driving is in the mountains going up and down in elevation. I just want to make sure to keep up with the maintenance so that I can make it to 500k. I 100% agree with what you are saying about a normal flush not being an issue. We have also discussed avoiding power flushes which like the plague.

I also agree that if a part is close to failure, I would prefer to have it go where it is hopefully easy to fix. Or in the event of the transmission, close to your shop!

Coolant I have seen a range in temps of between 173 to as high as 198. The average is right around high 170s to low 180s when moving. The 198 was when I was moving slowly on trails in Moab and it was full sun and about 95 degrees. Even that was only for a moment before it came back down to the mid 180s.

Trans temps seem to be between 135 to 165 in normal highway usage. When going over mountain passes or climbing off road I need to lock it in a lower gear to keep trans temps in check. Without locking the gear, trans got up to about 215 when going over Monarch Pass. That is the highest I have ever seen the temp go. I usually maintain higher trans temps off road because of all of the climbing. I now make sure that trans temps never go above 190. If they start getting into the upper 180s, I will usually switch over to low range. This will cause the temps to drop quickly back into the 150s usually.
You're to kind!

Any fuel smell or fuel boiling happening at the higher ECT?

If the engine coolant temp (ECT), is as low as 173F to 182F after warm up. Than likely time for a new OEM thermostat & gasket. 198F is not to bad for those condition. But consider washing the radiator fins from outside. That may drop your high ECT down a bit. You'll need to pull the #1 skid. I've a 90 deg wand, like the kind for cleaning gutters I use. I get in between fan balds and wash outward, underneath and wash up between AC & engine radiators and from the front.
 
You're to kind!

Any fuel smell or fuel boiling happening at the higher ECT?

If the engine coolant temp (ECT), is as low as 173F to 182F after warm up. Than likely time for a new OEM thermostat & gasket. 198F is not to bad for those condition. But consider washing the radiator fins from outside. That may drop your high ECT down a bit. You'll need to pull the #1 skid. I've a 90 deg wand, like the kind for cleaning gutters I use. I get in between fan balds and wash outward, underneath and wash up between AC & engine radiators and from the front.
I cannot say that I notice any additional fuel smell when at running temp. I am actually getting MPG of about 15 mpg up to about 70 MPH which is impressive given the ~7200 lb weight, the 34" tires and the aerodynamics of a brick. Fuel mileage got better after we did the tuneup.

What do you consider good ECT temps? I was thinking that staying at about ~177 most times was a good temp. This truck had the thermostat/gasket changed about 32k miles ago. It also has a different thermostat because of the supercharger. It is a TRD 160 degree thermostat. P/N 00602-17620-440.

I should definitely give the radiator fins a once over with all of the dust and crap that I drive through. That would certainly help to optimize the system. I also have some hood louvers on order too. Yeah, I am going to be that guy, but I am just amazed at how high the temps can get under the engine when I push it or just idiling the truck in desert temps. At those points the ECTs are staying in line, but I just feel bad for all of the plastic under the hood in all of the heat. I believe that the louvers will help to keep things in check.

*Edit* I was thinking about this more. Those temps that I posted are my Summer temps. I guess that my real range is usually more 165-198 if I include my winter temps. My winter temps tend to remain in the higher 160s, but I don't drive my truck much in the winter.
 
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I cannot say that I notice any additional fuel smell when at running temp. I am actually getting MPG of about 15 mpg up to about 70 MPH which is impressive given the ~7200 lb weight, the 34" tires and the aerodynamics of a brick. Fuel mileage got better after we did the tuneup.

What do you consider good ECT temps? I was thinking that staying at about ~177 most times was a good temp. This truck had the thermostat/gasket changed about 32k miles ago. It also has a different thermostat because of the supercharger. It is a TRD 160 degree thermostat. P/N 00602-17620-440.

I should definitely give the radiator fins a once over with all of the dust and crap that I drive through. That would certainly help to optimize the system. I also have some hood louvers on order too. Yeah, I am going to be that guy, but I am just amazed at how high the temps can get under the engine when I push it or just idiling the truck in desert temps. At those points the ECTs are staying in line, but I just feel bad for all of the plastic under the hood in all of the heat. I believe that the louvers will help to keep things in check.

*Edit* I was thinking about this more. Those temps that I posted are my Summer temps. I guess that my real range is usually more 165-198 if I include my winter temps. My winter temps tend to remain in the higher 160s, but I don't drive my truck much in the winter.
In stock is a 180F (82C) thermostat. I see 184-189 avg 187F. I was unaware you use a 160f thermostat, with your TRD package. So seems thermostat is good.
 
In stock is a 180F (82C) thermostat. I see 184-189 avg 187F. I was unaware you use a 160f thermostat, with your TRD package. So seems thermostat is good.

Wow that is a big difference in the trigger temp on the thermostat. I didn't realize that it was that big.
 
For the 4spd, which is preferable:

Mobil 1 synthetic ATF

or

Mobil MV ATF

I see lots of words referencing both, but no links to products. I'd like to procure the preferred poison.
 
Perfect, thank you folks. I'm humbled by the knowledge base on here :beer:
 
I've read all the transmission threads I could find to change my fluid on an 2006 LX. I am still confused as to which hose to unplug, and where I should put the hose extension to drain the fluid. People refer to outlet/inlet but its not clear what diagram they may be referencing aka if its outlet from tranny or tranny cooler. On this attached picture do I remove the top hose(red line) from the transmission cooler and attach a drain hose from the transmission cooler(where I removed the hose) to my dirty drain bucket?

From there run the engine for a few seconds and refill( I don't have dipstick, I'll crawl back under) I understand how to measure proper level by getting coolant temp to proper range and then seeing if fluid comes out the overfill plug on the transmission. Will this get all the fluid out of the tranny cooler as well?

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If it helps any, i removed the grill on my 2006 (3 phillips head screws) and afterwards easily was able to use pliers on a hose clamp to slide it back. Hose nipple (as you are looking at area behind the grill) is on the lower left pointed towards driver side.
Not sure where it is in your diagram but i flushed 14 quarts of atf ws two quarts at a time using that hose. Did that just a few days ago.
 
First I've never done a Tran flush, but i believe the confusion stems from the diagram.
First the red ( hot) & blue (cool) are reversed in the picture. i think steming from the confusion for "inlet/outlet" as indicated on the diagram. I believe it is refering to the trans cooler inlet/outlet not the transmission's.
Second the dotted line don't match up when you follow it to Tran cooler.
2001LC says to pull the hose which he points to above, but if you follow that hose to the tran cooler it appears to lead to the upper hose at the Tran cooler.
But it's not it actually leads to the lower hose at the cooler.
So when Ducknl says he removes the lower hose he's also right.
So either pull the lower hose at the Tran cooler or the one 2001lc points to because they are the same hose (trans cooler outlet) IOW the cool line heading back to the transmission
I hope I got that right.
 
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Pulling the return hose pictured and attaching a drain hose to catch bucket, at hard line next to radiator and near airbox. Is last point before fluid returns to transmission. It's first point after the transmission oil cooler radiator, easily accessed by just opening the hood. You can follow this hose to hard line and disconnect just under alternator. But that spot is not as accessible, messy and requires remove skid plate. In either case you'll no you've the correct line, when you idle the engine.

Some videos in youtube, show disconnect line going into radiator (DS engine coolant radiator). That not optimal point to drain from. As it does not flush radiators, and is messy. But, if you didn't have a drain hose to hook-up and run to a catch can. It's an easy point to run/drop its hose, directly to a catch can under the vehicle. It requires removing the skid plate for easy access.
 
Thank you both. The picture was worth a thousand words. I saw that hard lose location when I was surveying the situation. This makes sense as it will help to drain the cooler as well. Trace bottom line hose from Tran cooler on its way back to transmission to the hard line location in the picture.

On a 2nd note I have the tiniest bit of rust located on these hard lines-is there any problem with prepping the surface and spraying a little rustoliem 500 deg engine spray paint on these?
 
I can't find thr fill bolt at all its 24mm head right? Stamped ws? Do I also need to remove front skid? Is this bolt it-that's been removed? It was missing when I started the job.

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This is for the A750F (5 speed), versions without dipstick:

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On my 2006, the fill bolt is marked “ws” and is 24mm.
 
I can't find thr fill bolt at all its 24mm head right? Stamped ws? Do I also need to remove front skid? Is this bolt it-that's been removed? It was missing when I started the job.

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Thank you both. Eventually I found it and drained the transmission-after significant delays.

I could not find the fill plug anywhere when I started and couldn't find a diagram for the life of me. I removed a smaller than 24 mm screw from the side of the transmission and tried to fill there with no luck. I know everyone said its really hard to fill and I agree. Fluid just came back out and did not take so I knew this wasn't right. I put the screw back back in. I was crawling my way back under the car and stumbled upon a 24 mm plug easily accessible. How did I miss it? Well I removed the transfer case fill plug by accident(changed that fluid last week or so) and proceeded to pump atf into it which was flowing out. After realizing my mistake I immediately drained transfer case and fluid looked just like new, not mixed with pink/red. The atf was flowing back out the fill plug like when you fill transfer case with gear oil.

Eventually I found the fill plug from a youtube video. It is easiest to see if you are further back towards the middle of the truck looking forward and up. It's next to impossible to see from the front of vehicle looking back. After draining the pan first(before even locating the fill plug, woops lesson learned) I removed the shift linkage to get easier access to fill plug and filled with 2 quarts(all that came out, slightly warmed up after drive) I d/c the outlet from the trans cooler aka lower line coming out of trans cooler to my drain bucket. Starting the car and drained away 3x to get 6 quarts out. The fluid was dark brown at first, didn't smell bad and got progressively more red quickly. By 6-8 quarts it was looking basically new, but I kept going since I had her opened up.

Now I wanted to move through the gears with foot on brake to get it all out as best I could. My dad was assisting and went P to R and fluid spewed out of the transmission. I thought I did not put the fill plug back in. But no, I had placed the "smaller than 24mm screw" I took out first in the wrong hole. There are 2 vacant screw holes, one on each side of tranny and I put it in the wrong one. It spewed hard all over cat etc. and clean up was fun. I figured out my mistake(number 2 of the day) and refilled, ran through gears with no spillage. Yay, small victories are nice.

I plugged in my Icarsoft to start monitoring a/t temperature. I am not certain, but I think it only shows engine coolant temp because engine coolant and a/t temp were the exact same(is this correct?) I was under impression they would have different thermostats and did not trust that Icarsoft was correct so I tried to jump the 4 and 13 pin at dtc but failed at that too. Engine on tried to jump, shift between D and N 1.5 sec for 6 times and could not get D light to come on.

The shift from D to N didn't feel like normal, a bit clunky so I added more fluid and was also checking "check" plug. A few drops came out of check plug earlier when engine was cooler but as I started and checked again it was mostly dry so I kept adding fluid. I did a road test after a few more small fills of 0.3-0.5 qt approximately and the truck shifts excellent, aka the exact same as before. As a precaution I shifted on the dirt to 4L and ran the truck in 4L and back to 4H-came home and drained more transfer case fluid which was not pink/red at all so I was happy about that.

The truck had 211k on the trans fluid and I don't think it was changed at all. The PO babied it but I don't think Lexus changes it out as part of service unless extreme conditions or you are towing.

I am going to buy the tool to jump the DTC so I can run through the proper procedure but it was a rough day to say the least. While the car was "cooling" so I could get to at least 46 Celcisus(again not sure if this was engine or a/t temp on Icarsoft) I changed the pcv valve with a 22 mm wrench. Tough to twist off but went smoothly compared to the transmission! The pcv valve had lots of black deposits on the lower part and inside, but the ball/valve was still clunking around.

Last question, I thought I saw proper temp is 36-46 to test the temperature. Did it used to be higher aka 46-56? What temperature does the truck "think" is correct? I thought I read the revised the fsm or a/t check temp so I am not sure if the car is "thinking" correctly. I know I was not today!
 
See post #152 above. You'll see I posted the TSB with new ATF topping temps 97- 115f. We do not use the jump procedure any longer. We read temp in tech stream 97-115 F. If you can't access tech stream. Shoot transmission pan with IR temp gun. Shoot for 100 to 105F.

Procedure is to shift through all gears once at temp. Once at temp, while idling with shifter in "N", remove check plug. If overfilled, ATF fluid will run out. If underfilled it will not run out. You want it slightly overfilled and let run out until it just drips. DONE.

I run a hose from under hood to fill plug. I don't remove linkage.
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You can reuse O-ring on fill plug, torque to 29dt-lbf. But replace crush washer on drain and check plug each, torqued each to 15ft-lbf.
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