8 Speed Transmission Serviced (850RE)

Jeep’n Jay

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In case anyone is interested. I serviced my "lifetime" fluid transmission at 26k miles. My transmission has always had a faint whine most noticeably in 2nd and 5th gears. It sounds like an alternator whining but it is indeed the transmission. Dealers and mechanics have said it is normal as these transmissions have planet gears, which apparently create some whine eventually. (Only going off what I have read and been told). I wanted to see if by servicing the transmission I could get rid of it. Long story short the whine is still there although it is not as noticeable.

A few things...... the JL DOES have a changeable filter. You do not need to change out the entire pan as you would have to on the RAM trucks, chargers, etc. Servicing the transmission is not any harder than any other transmission you may have serviced in the past. There are a few additional steps to fill it or check the level, but it is not really that bad at all. I put in an additional 3/4 quart than what came out. I believe this has probably been low from the factory. There were no metal shavings, etc. in the fluid just the dirty clutch material, the magnets were pretty full with the sludge. The fluid was black coming out. Probably to be expected since new the fluid is clear, but I wasn't expecting it to be as black as it was. I did add lubegard platinum to my fill. It is the only additive I have ever ran in a transmission and is fully compatible with the 8 speed ATF by MOPAR.

For anyone interested here is a video of the process:

JL Transmission Service

 

Dave928

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yeah nothing is "lifetime". mine whines in reverse. i'll probably have it serviced @ 50k.

where did you get the pump for the oil bottles?
 
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wibornz

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Great video. I will be doing this soon. So only thing I need is the filter, 5 qts of fluid and the pan gasket?
 

CarbonSteel

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Nice video, thanks for posting. For clarity, this is not a complete fluid replacement is it? I'm guessing you could do the "turkey baster" method where you add these five quarts, drive for a few thousand miles, dump it again and that should kind of get you a good percentage of fluid that is replaced.

I plan to do mine around 40K (at 36K now) just for piece of mind.
 
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Jeep’n Jay

Jeep’n Jay

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Great video. I will be doing this soon. So only thing I need is the filter, 5 qts of fluid and the pan gasket?
Yes that is all that is needed for a service. I bought my ATF off of Amazon as it was less expensive than the dealer. 7 quarts was $158, about $30 for the filter, and $40 for the gasket. Wasn't sure how much fluid I would need is reason I bought so much.
 


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Jeep’n Jay

Jeep’n Jay

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yeah nothing is "lifetime". mine whines in reverse. i'll probably have it serviced @ 50k.

where did you get the pump for the oil bottles?
That is the $10 pump from Autozone, worked great.
 
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Jeep’n Jay

Jeep’n Jay

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Nice video, thanks for posting. For clarity, this is not a complete fluid replacement is it? I'm guessing you could do the "turkey baster" method where you add these five quarts, drive for a few thousand miles, dump it again and that should kind of get you a good percentage of fluid that is replaced.

I plan to do mine around 40K (at 36K now) just for piece of mind.
Correct, I assume the torque converter was full of old fluid. Driving around for a few thousand then doing another drain and fill would be ideal. I don't plan on doing it again until 50k however.
 

CarbonSteel

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Correct, I assume the torque converter was full of old fluid. Driving around for a few thousand then doing another drain and fill would be ideal. I don't plan on doing it again until 50k however.
How thick is the pan? I am assuming it is metal? I am thinking about adding a drain plug to mine when I do the initial change. This would allow me to drain it without dropping the pan for those times when I want the only change the fluid and not mess with the filter.
 
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Jeep’n Jay

Jeep’n Jay

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How thick is the pan? I am assuming it is metal? I am thinking about adding a drain plug to mine when I do the initial change. This would allow me to drain it without dropping the pan for those times when I want the only change the fluid and not mess with the filter.
I think the pan would be plenty strong enough to support an aftermarket drain plug, the problem I would see is the clearance underneath or to the side of the filter. The filter sits in the lowest part of the pan, not sure there is enough clearance underneath it for the plug. Would be interested to know however, I think a low point drain plug would be a great addition.

tempImagePnGKCz.jpg
 

CarbonSteel

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I think the pan would be plenty strong enough to support an aftermarket drain plug, the problem I would see is the clearance underneath or to the side of the filter. The filter sits in the lowest part of the pan, not sure there is enough clearance underneath it for the plug. Would be interested to know however, I think a low point drain plug would be a great addition.

tempImagePnGKCz.jpg
Provided it was not a typo, I just ordered a new pan from RockAuto for $2.37 ($17 to the door with tax and shipping) and I am thinking that one of these may fit with no clearance issues:

Screenshot_20211009-092925_Chrome.jpg
 


D60

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Would be interested to know how fluid temp compares on a scan tool vs dash. Maybe I'll check this out.....if I remember
 

sureman

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Great video. Thanks for taking the time to record it.

My plan is to drop the pan, new filter, gasket, fluid then 10k later just suck the fluid out of the fill hole. How much fluid do you think will come out? Maybe do this again at another 10k. Thoughts?
 
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Jeep’n Jay

Jeep’n Jay

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Great video. Thanks for taking the time to record it.

My plan is to drop the pan, new filter, gasket, fluid then 10k later just suck the fluid out of the fill hole. How much fluid do you think will come out? Maybe do this again at another 10k. Thoughts?
My best unscientific guess is 3-4 quarts. The main issue is the fill hole is above the filter so I don’t think you would get to the very bottom of the pan. But it would be close enough in my opinion.
 

blnewt

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Great job there Jay, don't know how I missed this thread as I've been dialed in to most all the ATF service threads :headbang:

Posted the question on the youtube site but if you check here too~
Do you happen to know the part # for the filter?
And the Lube Gard addition, I assume just for some added piece of mind? Never used any ATF additive so just curious.
Thanks for the great info!

 

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