No need to change transmission fluid for the life of the truck...REALLY?

[heffy]

I was looking at the service intervals for my Eco Diesel and it says transmission fluid should last the trucks life without changing. I've always change the filter and fluid every 75,000 miles on past trucks. I do have a 5 year 200,000 mile Max Care extended warranty. If I the trans makes it that long without failing, I'd be worried changing the fluid & filter at that time (always been told if you don't change it before 125,000 miles leave it be, as you run the risk of loosing up crud that has built up in the case) Any transmission specialists out there that have an opinion?

 

[Darksteel165]

I was looking at the service intervals for my Eco Diesel and it says transmission fluid should last the trucks life without changing. I've always change the filter and fluid every 75,000 miles on past trucks. I do have a 5 year 200,000 mile Max Care extended warranty. If I the trans makes it that long without failing, I'd be worried changing the fluid & filter at that time (always been told if you don't change it before 125,000 miles leave it be, as you run the risk of loosing up crud that has built up in the case) Any transmission specialists out there that have an opinion?

You can't run it forever. "For life" is a sales\engineering term. The "life" of a truck is determined by a set amount of miles, generally what the warranty is.

I believe for these trucks you are suppose to change the transmission fluid every 100k miles.

Find what transmission you have, and look at what the manufacture recommends. Ram doesn't make transmissions.

 

[jkm312]

How "hard and what conditions" you use the truck will determine when the fluid needs to be changed. If you max the truck out pulling at limits with a camper, change it sooner than someone who uses it hardly at all. That's the advantage of a dip stick for the transmission, you see what the fluid looks like and smells like.

 

[Darksteel165]

How "hard and what conditions" you use the truck will determine when the fluid needs to be changed. If you max the truck out pulling at limits with a camper, change it sooner than someone who uses it hardly at all. That's the advantage of a dip stick for the transmission, you see what the fluid looks like and smells like.

Could always take off the fill plug and shove your finger up there if you want to see how it looks or smells, lol.

Unfortunately most vehicles don't have dipsticks for trannys, it's too bad.

 

[c3k]

There's a lot of information about the ZF8HP75 transmission in your truck on the forums.

The transmission pan has magnets and a filter built into it. You need to change the entire pan to change the filter. You'll get about 1/2 the fluid if you drain and fill. ZF says 100,000 miles fluid life produces "an acceptable rate of failure." Me? I'll be doing a fluid swap at 40k. (I'll drain and fill 3-4 times. 3 times means I'll get ~87.5% new fluid into it: 4 means ~93.75%. A brief drive between each drain and fill will mix the fluid left behind in the torque converter.)

 

[2021EcoDiesel]

Exactly, Ram says the fluid is good for the "life" of the truck I can promise you that you will get a shorter "life" if you never change the fluid. I'll be doing my own at 50,000 miles and probably every 50-75k after that. its not a job for rocket scientists but it does take some mechanical know how and some patience. And definitely listen to ZF's service recommendation they sell millions of transmissions per year, Ram is only a small piece of their pie.

 

[jkm312]

Could always take off the fill plug and shove your finger up there if you want to see how it looks or smells, lol.

Unfortunately most vehicles don't have dipsticks for trannys, it's too bad.

Nope! The proper place for us oldster's is IN the cab, NOT under the truck.

 

[John Jensen]

Ram considers the tranny's lifetime to be 100,000 miles.
Forum members have reported that the tranny's manufacturer recommends 50,000 miles.

 

[Darksteel165]

Nope! The proper place for us oldster's is IN the cab, NOT under the truck.

I'm confused.
What exactly are you doing inside the cab of the truck with the transmission? Temperature of the trans oil? I have that in my truck.
Are you looking for a mile counter that tells you it's time to change is based upon the mileage on your truck like a change oil light?

You will just need to mark down the last time you changed the trans oil.

 

[WXman]

I'm pretty sure 150,000 miles is what engineering considers "life time" on a light duty pickup.

Obviously the correct way is to replace the filter and fluid every 60k per ZF's own specification, but good luck finding a dealership willing to do that. They all want to hook their machines up to the cooler lines and run fresh fluid in without even dropping the pan and then charge you hundreds of dollars for it.

 

[AV8OR]

Ok it’s raining outside so crawling under my truck isn’t happening today..

So for the sake of argument:

(1) How do you drain the oil, old school drop the pan with all the fun that goes with it?

(2) How do you fill it if there is no dipstick / filler tube?

(3) How many quarts to you put in it?

(4) Part numbers for filter and gasket?

 

[Darksteel165]

Ok it’s raining outside so crawling under my truck isn’t happening today..

So for the sake of argument:

(1) How do you drain the oil, old school drop the pan with all the fun that goes with it?

(2) How do you fill it if there is no dipstick / filler tube?

(3) How many quarts to you put in it?

(4) Part numbers for filter and gasket?

#1 Drop the pan and attempt to not wear oil
#2 just above the pan on the side is a fill plug, need to squeeze the bottles or somehow get it above it to gravity feed. It's fill when you can't put anymore in. There are some things about running the oil to a temp and then adding more until it meets the fill plug(and starts to come out)

#3 and 4 someone else would need to respond.

Here's a video on how to check the fluid level

There are videos on Youtube on people changing the oil by dropping the pan, lots of detailed videos but it's pretty basic from what I can see.

 

[Darksteel165]

I'm pretty sure 150,000 miles is what engineering considers "life time" on a light duty pickup.

Obviously the correct way is to replace the filter and fluid every 60k per ZF's own specification, but good luck finding a dealership willing to do that. They all want to hook their machines up to the cooler lines and run fresh fluid in without even dropping the pan and then charge you hundreds of dollars for it.

Where are you seeing 60k miles per ZF's spec?

This is showing 93km (150km)

https://aftermarket.zf.com/remotemedia/master-content/zf-services-portal/oils-data-sheets/pc-1/lifeguardfluid-8/pds-zf-lifeguardfluid-8-it.pdf

I also found these quotes from ZF but I don't have the source.

"A lot of discussion has occurred on the topic of oil change intervals for ZF transmissions. It is important to adhere to your vehicle manufacturer specified change interval and it is very important to use authorized fluids. ZF Lifeguard fluids are designed and tested to retain characteristics through normal lifetime operating conditions; per the OE vehicle manufacturer specifications"

"In instances of extreme driving conditions, special environmental considerations, and driving factors which place an increased load on the transmission, it is advisable to perform a drain and fill between 50k and 75 miles, or 8 years."

This video is for a ZF6 not ZF8 but it shouldn't matter based upon the above referenced PDF for ZF8.

The video also confirms what I said above about filling it, then running it to temp and then checking it.

 

[WXman]

Where are you seeing 60k miles per ZF's spec?

This is showing 93km (150km)

https://aftermarket.zf.com/remotemedia/master-content/zf-services-portal/oils-data-sheets/pc-1/lifeguardfluid-8/pds-zf-lifeguardfluid-8-it.pdf

View attachment 145108

I also found these quotes from ZF but I don't have the source.

"A lot of discussion has occurred on the topic of oil change intervals for ZF transmissions. It is important to adhere to your vehicle manufacturer specified change interval and it is very important to use authorized fluids. ZF Lifeguard fluids are designed and tested to retain characteristics through normal lifetime operating conditions; per the OE vehicle manufacturer specifications"

"In instances of extreme driving conditions, special environmental considerations, and driving factors which place an increased load on the transmission, it is advisable to perform a drain and fill between 50k and 75 miles, or 8 years."

This video is for a ZF6 not ZF8 but it shouldn't matter based upon the above referenced PDF for ZF8.

The video also confirms what I said above about filling it, then running it to temp and then checking it.

Some guys on the HD forum (who also have ZF 8HP75 transmissions) were discussing it and brought out the factory service manual from ZF. They were quoting a 60k mile interval on fluid, which matches what we used to always see on other auto transmissions in the U.S. in decades past.

 

[Darksteel165]

Some guys on the HD forum (who also have ZF 8HP75 transmissions) were discussing it and brought out the factory service manual from ZF. They were quoting a 60k mile interval on fluid, which matches what we used to always see on other auto transmissions in the U.S. in decades past.

HD trucks are not LD trucks.
HD trucks are designed to be pushed hard. 1500s are not. The manufacturer says if under heavy duty to be changed more frequently, which could be perceived as 60k,

I'm going to go with the information from the manufacture vs another forum for a truck designed for a different life.

 

[John Jensen]

View attachment 145108

150,000km = 93205.6788 miles. Pretty close to the reported Ram lifetime being 100,000 miles

 

[c3k]

Ok it’s raining outside so crawling under my truck isn’t happening today..

So for the sake of argument:

(1) How do you drain the oil, old school drop the pan with all the fun that goes with it?

No. That is old school Chrysler crap. (Who eff EVER makes a pan without a drain plug? Seriously.)

The plastic tranny pan has a drain plug. Open it. Wait for the pink/red fluid to stop coming out. Put it back in. Undo ~13 bolts. Bob's your uncle! You're now looking up at wet valve body.

Edited to add: Not pink/red. Sorry. Light oily.

(2) How do you fill it if there is no dipstick / filler tube?

Just above that pan is a bolt. It's plugging a fill hole. Put the new pan on. (Yeah, it comes with a drain plug already installed.) Undo the bolt on the fill hole. Pump your fluid in. (There's some specs about temp. Psh. Look it up.)

(3) How many quarts to you put in it?

From memory (a year+ ago) about 5. (<- do NOT take that to the bank. That's a ROUGH approximation.) Look it up. Fill it until it drains out. Again, at a certain fluid temperature.

(4) Part numbers for filter and gasket?

Not at hand.

Edited to add: I use LiquiMoly's ZF fluid. Specced for it, and MUCH less expensive. $8 a liter?

 

[SD Rebel]

Not sure what the argument here is, the manufacturer/designer of our transmissions recommend 50K - 70K service.

Clearly everyone here interested in keeping their trucks healthy are going to do that service within that timeframe (assuming you keep your truck that long) instead of a "lifetime" non-service the dealer recommends, since your tranny will likely at least survive beyond any extended warranty period.

Though to be specific, I think Stellantis produces our ZF8s under license. However I don't think Stellantis does anything that would somehow extend the range of the tranny's service interval beyond the original design.

 

[jkm312]

I'm confused.
What exactly are you doing inside the cab of the truck with the transmission? Temperature of the trans oil? I have that in my truck.
Are you looking for a mile counter that tells you it's time to change is based upon the mileage on your truck like a change oil light?

You will just need to mark down the last time you changed the trans oil.

My point was and is, my wrenching days are over except for the simple easy to get to stuff like batteries, air filters, cabin filters etc. For those of you who like to do all of your service work, good for you. I was once just like you, but I've enjoyed all I want of it. I know when the truck needs to be serviced, and have good people in good shops to do that for me.

 

[GKIII]

Not sure what the argument here is, the manufacturer/designer of our transmissions recommend 50K - 70K service.

Clearly everyone here interested in keeping their trucks healthy are going to do that service within that timeframe (assuming you keep your truck that long) instead of a "lifetime" non-service the dealer recommends, since your tranny will likely at least survive beyond any extended warranty period.

Though to be specific, I think Stellantis produces our ZF8s under license. However I don't think Stellantis does anything that would somehow extend the range of the tranny's service interval beyond the original design.

The V6 transmissions are produced under license (850RE = Stellantis licensed 8HP transmission). The V8s (and EcoD) use ZF-manufactured units.