Transmission Fluid Lessons

[bigcheeshead]

My transmission temps have been hot for over a year now, typically in the 220’s during regular highway use and 240-260 while towing a 4,000 pounds RV. Finally decided to do something about it and:

• Installed Mishimoto transmission cooler
• Replaced OEM transmission pan (It was leaking badly and never had a gasket installed from the factory) with PFE heavy duty pan + OEM gasket.
• Replaced transmission fluid with Red Line D6 as recommended by Extreme Terrain. It took nearly 2 gallons / ~7 quarts to fill up! Is that too much? My original transmission fluid was Vantablack and burnt to a crips, see pic.

OMG what a difference! Shifting is silky smooth, no weird screeching noises or shaking. I also drove for over an hour today and never went above 186 degrees no matter how hard I tried. I just hope that I stopped the bleeding before permanently F$#* up my tranny. Lesson learned, if you’re wheeling hard and/or towing in hot places like AZ:

• Install a transmission cooler.
• Replace transmission fluid every 30K or so and ignore the “lifetime transmission fluid” claim by Jeep! My 2020 JT is still under 40,000 miles!

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[Hootbro]

(It was leaking badly and never had a gasket installed from the factory)

So the pan was RTV'd? That is highly suspect if it had no gasket. I doubt it actually left the factory that way and there was some shenanigans after the fact with either the dealer or if somebody else was servicing it for other reasons.

 

[Maximus Gladius]

I would 2nd @Hootbro reply. Let’s hope your proactive maintenance delayed its early death. You didn’t by chance send a sample of that oil to Blackstone labs or Polaris labs?? Would have loved to see where the wear metal counts were before you did this.

How do you feel about knowing the torque converter had 4 litres of the old crap in there mixing with the new? That would bug me and I’d probably do another pan drop soon to get more of it out.

I noticed your new temp #’s. Is the 186 F typical now for on road and off road/wheeling? Since I got my 4th tranny, (no aftermarket cooler/pan) my typical “on road” temp stays at and under 88c (190F).

My speculating brain is dissecting this and this is where an oil analysis would have played a huge part in gathering data on the condition of your transmission.

You mentioned your temps only getting to 186 no mater how hard you try. I wonder where it would be if all you did was change the oil. ?? I’ve seen Northridge 4x4 do an install of a pan like yours and having to file down the heat fins for the exhaust pipe to fit the pan. The exhaust pipe is pretty much touching the pan

I haven’t seen this aftermarket cooler you installed but I’d bet it’s better than OEM … it’s just that your numbers and mine are “the same” for the most part. An oil analysis would explain why after adding heat displacing improvements, the numbers are where they would normally be at the end of the day.

No doubt you did a very good thing and the result is you lowered your operating temps. ??

 

[willys 41]

If you want to also keep your oil / coolant /trans temps down I highly recommend the
RpmExtreme Jeep JL PWM FAN CONTROLLER
It is a game changer as far as keeping all temps down
I have see 25 to 30 coolant and oil temps and my trans temp has never gone over 206 and my coolant has never gone over 212
Here is how it works


NORMAL CANBUS OPERATION
When the engine is running the PWM fan will run at a low Idle speed (15%).
When the module reads the engine temp it will command the fan to the desired %.

Fahrenheit
199 degrees = 30%
205 degrees = 50%
212 degrees = 75%
218+ degrees = 100%

http://www.rpmextreme.com/Product/311/Jeep-JL-PWM-FAN-CONTROLLER.aspx

 

[SoK66]

I notice on our tour JTs what I consider rather high 200+ trans temps. The trans cooler looks rather skimpy, so adding an auxiliary like we do on first gen JKs seems perhaps a good move. The JL/JT trans is a superb unit, no sense in burning it up. Not sure why ET would recommend Redline when spec is a special ZF ATF.

Would add that if you have an aux trans cooler added you can do the old "hillbilly" trans flush. Separate the return line at a connection (cap off the other side), put a length of hose from the return line into a plastic milk jug with a 2QT line marked clearly. Start up the engine, let the jug fill up to the line & shut it off. Dump out the old fluid, add 2 fresh qts to the trans. Repeat until you've removed and added the equivalent of a full trans fluid change. You'll get about 85-90% of the old stuff out, which is way more than if you just drop the pan and refill.

 

[bigcheeshead]

I notice on our tour JTs what I consider rather high 200+ trans temps. The trans cooler looks rather skimpy, so adding an auxiliary like we do on first gen JKs seems perhaps a good move. The JL/JT trans is a superb unit, no sense in burning it up. Not sure why ET would recommend Redline when spec is a special ZF ATF.

Would add that if you have an aux trans cooler added you can do the old "hillbilly" trans flush. Separate the return line at a connection (cap off the other side), put a length of hose from the return line into a plastic milk jug with a 2QT line marked clearly. Start up the engine, let the jug fill up to the line & shut it off. Dump out the old fluid, add 2 fresh qts to the trans. Repeat until you've removed and added the equivalent of a full trans fluid change. You'll get about 85-90% of the old stuff out, which is way more than if you just drop the pan and refill.

Had me worried about the fluid for a second. Did little more digging and found out that ET specifically states that D6 meets Jeep & ZF specs, see comment at 7:12 of the video below:


I've also confirmed on Red Line site that R6 is compatible with the JT.
Red Line has no issues mixing with OEM fluid and although it was pitch black, I didn't see any metal shavings in it. I figure having a quart or less of the old fluid shouldn't make that much of a difference.

 

[Maximus Gladius]

Had me worried about the fluid for a second. Did little more digging and found out that ET specifically states that D6 meets Jeep & ZF specs, see comment at 7:12 of the video below:


I've also confirmed on Red Line site that R6 is compatible with the JT.
Red Line has no issues mixing with OEM fluid and although it was pitch black, I didn't see any metal shavings in it. I figure having a quart or less of the old fluid shouldn't make that much of a difference.

I’m not sure if you have warranty still or not but I’ll tell you about my real story using Amsoil ATF in my ZF 850RE tranny. Amsoil and me go way back to the 1980’s and had full confidence in the product and even was willing to bet the farm on it so when I had a chance, I flushed the transmission and replaced the fluid with Amsoil….. but not before checking with Amsoil if it complied with the Chrysler/Mopar specs for the transmission. Amsoil said “it sure does”, in fact they then provided me with their own spec sheet of compliance codes which listed this transmission and it even states on their spec sheet that “they recommended using their ATF if we had any of the numbers listed”.

Had the flush done at 24k kms at the expressed warning of my service manager and once I did it, the transmission shifted so nice and buttery smooth. It operated strong for the next 8k kms …then blew up.

The service tech noticed the oil was red instead of green and Chrysler threw the book at me and refused warranty. Amsoil coward away and my last words with them is they might have recommended the use of their ATF but ZF refused it and said Amsoil was not an “equivalent oil” to the Mopar 8/9 speed ATF, therefore Amsoil’s spec sheet is a false document. They had nothing to say and I had to figure out my own replacement.

The point to this is you want to go onto ZF’s website and search for their customer care email and ask them if the brand of oil you put in their is an equivalent oil to use and approved. You may say that ‘of course ZF will say to only use their oil’. Not true, they have a section in their website that shows that other oils can be used except when it comes to this specific transmission. I’ve been back and forth with ZF’s North American customer care department and their is no other oil recommended for use in our 850RE.

How far is the place that recommended their oil to be used to go to bat for you if something bad happens? It’s only about 10k + $$ to replace it.

 

[bigcheeshead]

So the pan was RTV'd? That is highly suspect if it had no gasket. I doubt it actually left the factory that way and there was some shenanigans after the fact with either the dealer or if somebody else was servicing it for other reasons.

Jeep had only 19 miles on it when I bought it so doubt the dealer would have any reason to replace transmission fluid. I put a full body steel skid plate system underneath right after a bought it and it's a complete pain in the #$*(& to remove. No one would've done it without me noticing

 

[Maximus Gladius]

Op, I also want to add that your torque converter holds more than “a quart or less” as you mentioned. It holds 4. With the larger pan you have, you’re probably using 10 quarts for the tranny, correct?? Unmodified holds 9. With having 4 quarts of old burnt oil still in there, that’s just under half is still the old crap.

I watched the video and see a couple major problems.
1. the Northridge guy is speaking in blind faith that the oil meets ZF’/Chrysler specs. If he actually did his homework and asked ZF if red line D6 was an “equivalent oil”, ZF would have said no. I can confirm the list of oils viewed as “equivalent” and approved by ZF does not list Red Line for any of the multiple transmissions they have.
2. When first filling the tranny, engine off, he fills till the oil dribbles out then starts the engine and waits till temp is reached. He just F$)!k’d the transmission by waiting all that time while the pump is sucking air. How do I know?

If the tranny is cold and you want to drain the oil, pull the fill plug and you’ll see a bunch of oil come out until the level drops to the bottom of the fill hole. That “extra” amount that just drained out is necessary to keep the pump full.

Now if you’re doing your first fill and can only fill to the bottom of the fill hole and you can’t put all that extra oil in, the pump is going to suck air. That guy waited way too long waiting for the right temp to put any more in.

 

[Hootbro]

Jeep had only 19 miles on it when I bought it so doubt the dealer would have any reason to replace transmission fluid. I put a full body steel skid plate system underneath right after a bought it and it's a complete pain in the #$*(& to remove. No one would've done it without me noticing

Still improbable it happened as a matter of course during either the transmission unit itself when manufactured or during install into the vehicle at the factory.

 

[bigcheeshead]

Thank you everyone for flagging the Red Line fluid!!! I just got off the phone with RedLine (great customer service BTW) who assured me that the specs on their fluid are nearly identical or exceed those of Mopar 8/9 ATF. HOWEVER, They are NOT certified by either ZE or Chrysler for use in the transmission!!! To ensure warranty coverage and to remove remainder of the old fluid, I'm going to do another drain. The PPE pen should make it super easy since it has the drain plug. The question is:
How long should I wait, ASAP or a few months down the road?????

@MaximusGladius I followed ET instructions to the letter, waiting for it to warm up then cycling the gears. What would you recommend doing differently instead?

 

[Maximus Gladius]

Thank you everyone for flagging the Red Line fluid!!! I just got off the phone with RedLine (great customer service BTW) who assured me that the specs on their fluid are nearly identical or exceed those of Mopar 8/9 ATF. HOWEVER, They are NOT certified by either ZE or Chrysler for use in the transmission!!! To ensure warranty coverage and to remove remainder of the old fluid, I'm going to do another drain. The PPE pen should make it super easy since it has the drain plug. The question is:
How long should I wait, ASAP or a few months down the road?????

@MaximusGladius I followed ET instructions to the letter, waiting for it to warm up then cycling the gears. What would you recommend doing differently instead?

I’m impressed you called Red Line and found out the oil isn’t approved by ZF/Chrysler. After all my shenanigans with Amsoil and their false data sheet, the Amsoil Tech instructed me to use the manufacturer spec oil for my second transmission for the duration of the warranty period and then “if the transmission is still working by then, it would be safe to switch out for the Amsoil ATF”. ?!! Really??

So OP, to ensure warranty for your transmission, it all has to go back to original parts including draining out the “red” oil and putting in the “green” mopar 8/9 speed ATF. If you have any hiccup with the tranny and have to take it in for service, the tech will first look to verify the oil level and here’s where they’ll see the colour change. This was when my warranty was turfed.

My guess is if they see the aftermarket cooler and pan, they’ll axe your warranty for that too but maybe that Magnuson Moss law kicks in here,…I don’t know. That law doesn’t work up here in Canada. I’m hoping others here can chime in on this.

So, how to address filling the tranny as much as possible to not have the pump suck air is easy. This can’t be done with the frame level like it’s supposed to be when checking the oil level.
The fill hole has to be angled higher than the front. This is achieved by either raising the ass end of the truck as high as possible OR the passenger front and back tire needs to be as high as possible to the drivers side. However way you choose, make the fill hole higher to get a couple more litres in there than if it was level.

If you had your OEM pan on, you’ll need 5-6 litres to do the job. Tranny hold 9. If you choose to keep the oversized aftermarket pan, add the extra litre or so for that too.

So, assuming we start frame level, you get 3 litres in there before it dribbles out. If the ass end is up high, as mentioned above, you’ll get another litre in there. Once the extra amount is in there and dribbling out, put the pug back in and level the frame with wheels up. Have a syringe tube large enough to hold at least a litre and fill it. (Never use an oil syringe that was used for anything else. It will contaminate the tranny oil.)

Start the engine and get your ass under there and pull the fill plug and shoot in that oil. Keep doing that till it dribbles out. Temps are cold, this is good. Plug the hole and bring it to the recommended proper temp and run it through the gears like the Northridge guy shows (he did that right) then pull the plug and let the excess oil dribble out.

You’re done.

 

[GlennBeck]

I have the PPE pan on order, and now after reading these posts I may chicken out of doing the job myself. I'll talk with the Jeep tech and see if them installing the pan and servicing the transmission with proper fluid by their own service tech will keep me in the good graces of the warranty gods.

 

[Stan H]

I have the PPE pan on order, and now after reading these posts I may chicken out of doing the job myself. I'll talk with the Jeep tech and see if them installing the pan and servicing the transmission with proper fluid by their own service tech will keep me in the good graces of the warranty gods.

My local dealer did the labor for 172.00. I bought gasket fluid and filter brought them to him and they had it done in about 1.5hrs.-2.0hrs.

 

[Stan H]

I have the PPE pan on order, and now after reading these posts I may chicken out of doing the job myself. I'll talk with the Jeep tech and see if them installing the pan and servicing the transmission with proper fluid by their own service tech will keep me in the good graces of the warranty gods.

My local dealer did the labor for 172.00. I bought gasket fluid and filter brought them to him and they had it done in about 1.5hrs.-2.0hrs.

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