4th Gen Ram 1500 ZF HP8 Transmission Servicing

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Read much of the recent thread on the BMW zf8 fluid change. Just wondering if any one here has done this change on their Ram 1500? I got the 3.6 Pentastar engine.
Manual says it's "lifetime" sealed transmission and they don't recommend changing. I've owned it a year and already have 30K miles. I'm thinking to change next year when I have almost 60K. Easy miles on truck, just daily commute, no towing.
I've seen a couple of YT videos but any suggestions from experience here appreciated. I don't have the lifetime warranty.
 
I don't own one of these - but I say now is a good time to change it just to get the initial junk out. Since you don't tow or work your truck, you could stick to the 60K plan and plan on swapping out the pan and filter assembly as well.

Stick to the Mopar 8-9 Speed Fluid or ZF Lifeguard 8, no reason to give Mopar a reason to void warranty. The biggest thing with these "sealed" trannies is being able to see how hot the fluid is with a scan tool or OBD-II dongle + app that can access the datastream for the right PID.
 
My Dakota has a dash readout for transmission fluid temperature, as well as engine oil temperature.

I have the pentastar and the ZF 8 speed too. What keeps me from changing my fluid is the expensive fluid and parts.


Fluid and filter
 
Originally Posted by stenerson
Read much of the recent thread on the BMW zf8 fluid change. Just wondering if any one here has done this change on their Ram 1500? I got the 3.6 Pentastar engine.
Manual says it's "lifetime" sealed transmission and they don't recommend changing. I've owned it a year and already have 30K miles. I'm thinking to change next year when I have almost 60K. Easy miles on truck, just daily commute, no towing.
I've seen a couple of YT videos but any suggestions from experience here appreciated. I don't have the lifetime warranty.


Do a search on UTube, there is a video from ZF itself where they tell you to change the fluid around 40K km, I can't remember the exact number and to disregard what the car manufacturer says.
 
Will definitely use oem fluid...Wow! And I used to complain about atf4 prices.
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Originally Posted by Pelican


Do a search on UTube, there is a video from ZF itself where they tell you to change the fluid around 40K km, I can't remember the exact number and to disregard what the car manufacturer says.

ZF is suggesting 8 year/100Km(60K mi) intervals for all their tranmissions.

https://aftermarket.zf.com/us/en/af...ts-and-products/oil-and-oil-change-kits/ - go to the FAQs.

BMW changed their service interval to 60K or so, after seeing their earlier 5HP/6HPs fail after the warranty is up.

Since the OEM fluid is expensive, maybe a 60K drain/fill with one pan/filter unit change is all that's needed to keep these happy, unless you're towing or working a ZF 6/8HP through the wringer. This is one case where I would stick to OEM.
 
stenerson, I'm in the same boat.

I've got a 2017 Ram 1500 pentastar with the 8HP45. I'm just over 36K miles. I've seen a few drain/fill youtube videos on Hemi powered Ram 1500s, where they ignored the pan drain plug because it's directly over an exhaust pipe and just dropped the pan full. On our pentastars, there's nothing obstructing the pan or drain plug at all, so it's kind of silly not to use it.

Even if you do a cold drain/fill, given the side mounted refill/level check port, you have to put a few quarts in, then start and idle the truck and continue filling until you add back in what you took out, or it starts dribbling out. If you pull the fill/level check plug with the engine off, the fluid level will be high and pour out.

Yes.. I know the proper way is to have the fluid temp within the range the book says and level the truck such that the transmission is perfectly level. I have yet to see someone or hear of anyone jack the arse-end of their truck up to make the transmission level to do this job.
 
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In this video it sounds like a tricky process. I heard dealers charge about 850 bucks to do it by the book. (changing the fluid pan/filter)
 
I've always thought if you exactly measure what you drain out and replace exactly the same amount how could you be wrong? How would anybody know concerning warranty? If it's "low" or "too full" well the factory did it. There are U-Tube videos out there that show it's not "voodoo" changing fluid in these transmissions anyway.
 
Originally Posted by oldhp
I've always thought if you exactly measure what you drain out and replace exactly the same amount how could you be wrong? How would anybody know concerning warranty? If it's "low" or "too full" well the factory did it. There are U-Tube videos out there that show it's not "voodoo" changing fluid in these transmissions anyway.


The flaw in that is assuming it was filled correctly initially. Also some of these fluids can expand rapidly when they get hot.
 
Originally Posted by bdcardinal
Originally Posted by oldhp
I've always thought if you exactly measure what you drain out and replace exactly the same amount how could you be wrong? How would anybody know concerning warranty? If it's "low" or "too full" well the factory did it. There are U-Tube videos out there that show it's not "voodoo" changing fluid in these transmissions anyway.


The flaw in that is assuming it was filled correctly initially. Also some of these fluids can expand rapidly when they get hot.


I covered that. Too low or too full it came from the factory like that. Who would know? Nobody checks the fluid level when bought new on anything. Maybe, just maybe, the engine oil. But no tech is going to check the trans fluid or rear end fluid. Brand new Charger SXT. Rear end was low when I drained and refilled it at 1500 miles is perfect example. The 190MM rear end holds 24oz's. I drained 21oz's out. 3oz's???? Big deal some would say. That's over 10% low. Does my ZF 8 speed automatic have the correct amount of fluid in it??? Who knows???
 
Originally Posted by stenerson
In this video it sounds like a tricky process. I heard dealers charge about 850 bucks to do it by the book. (changing the fluid pan/filter)




I hear you, but you can make it out to be as tricky as you want.

If these ATs had a dipstick like they did for eons, all you'd have to do is keep the level within the range shown on the dipstick with the engine idling warm and in park. A lot of sticks were even labeled separately to measure the ATF level cold or hot. The rate at which these ATFs "expand when warm" hasn't changed.

I guess "sealed" or dipstick-less ATs don't freak me out as bad as they do many hammer mechanics like myself. The first one I owned, did drain/fills and level checking on was in 2002, even before my BITOG days!
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Originally Posted by PPWarrior
Being a Ram (Chrysler) I would change that crap every 6 months


Would you do the same in a VW, BMW, the new Supra, Audi, Jaguar, Aston Martin, or one of the various other manufacturers using a ZF 8HP transmission?
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Originally Posted by PPWarrior
Being a Ram (Chrysler) I would change that crap every 6 months


I've had good luck with Chrysler for the last 20 years. But I'm grateful that they have a bad reputation among many.
That has allowed me to buy them at very discounted/depreciated prices.
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The pans seem fairly shallow compared to the 3rd gen I owned. Anyone know approximate quarts lost in a cold drain and fill?
 
Originally Posted by kschachn
I have a better idea, why don't you just stop with your crap instead?


Agreed. Just another read tester parroting internet hearsay.
 
Originally Posted by MCompact
Originally Posted by kschachn
I have a better idea, why don't you just stop with your crap instead?


Agreed. Just another read tester parroting internet hearsay.


Actually a bit milder under his new name ...
 
Originally Posted by 4WD


Actually a bit milder under his new name ...


And a very appropriate user name at that.
 
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