Should we even change transmission fluid at all?

[Bpebler]

Question for experienced users & techs here as I couldn’t find anything specific or users that go by this methodology. This is my 2nd 5th gen Ram in the last couple years & came from a 2013 5.3 Silverado before that - currently also own a 2000 Jeep Cherokee XJ that is built for trails. The Jeep has 270k on the transmission & has never seen a fluid change & should keep rocking & rolling just fine without one for a long time. So I’m coming from the old way of thinking that transmission fluid changes are usually bad, losing the varnishes they build over time, have usual issues after changing fluid, yadda, yadda, yadda. Friends & family who are mechanics usually reinforce this. Tundra’s have sealed units that see several hundred thousand miles without issue as an example also.

Does this way of thinking also apply to our Rams? Anyone with a lot of mileage on their 5th gen that can vouch? I ask bc I know someone with a transmission shop in town. I can simply pay him for the “service” to show record that it was done to keep from voiding warranty & not actually have the fluid changed.

Maybe a fluid & filter change is actually beneficial on these but I simply don’t know. Any experienced feedback would be helpful. I’m only at 30k miles right now but at 6 months of use since new so I’m just preparing for when that time quickly approaches. Thanks in advance!

 

[wegasque]

Have you asked your buddy with the transmission shop for his professional opinion? Ask him what he'd do if it was his truck?

 

[SD Rebel]

As you mentioned, old school thinking is if the tranny fluid wasn't changed regularly, then probably not a good idea to change when it's too late, it could do more damage.

However, ZF has a very established maintenance interval for their ZF8 line of transmission. It's recommended at about 70,000 miles or so. RAM I think has it at 100K or so, I highly recommend you follow ZF's recommendation.

 

[Bpebler]

Have you asked your buddy with the transmission shop for his professional opinion? Ask him what he'd do if it was his truck?

I haven’t yet. I wanted to ask some forum members first. I definitely will though when I get the opportunity.

 

[Bpebler]

As you mentioned, old school thinking is if the tranny fluid wasn't changed regularly, then probably not a good idea to change when it's too late, it could do more damage.

However, ZF has a very established maintenance interval for their ZF8 line of transmission. It's recommended at about 70,000 miles or so. RAM I think has it at 100K or so, I highly recommend you follow ZF's recommendation.

I will consider this then. I changed my Silverado’s transmission fluid per manufacturer recommendations at the first interval & had problems that weren’t 100% corrected even after the dealer threw about 4k in warranty repairs.

 

[HSKR R/T]

Its very beneficial to change trans fluid at regular intervals. Even on older transmissions. Your jeep would probably thank you to get some fresh fluid and a filter. If the transmission ****s the bed after a fluid/filter changed then it was already on its way to failure.

Every 60-70k miles is a good change interval.

 

[theblet]

When you have this done, make sure the shop does a trans fluid FLUSH, not just a change. Just changing it will not remove all of the old fluid.

 

[Rebelguy2020]

The transmission fluid is in there for the life of the vehicle for normal operating conditions. Took this image from my 2020 manual.

 

[HSKR R/T]

When you have this done, make sure the shop does a trans fluid FLUSH, not just a change. Just changing it will not remove all of the old fluid.

I would say do a flush every other time, or buy some extra fluid, drop the oanz change filter, drive truck for a couple days, drop the oan again, and refill.

 

[Bpebler]

The transmission fluid is in there for the life of the vehicle for normal operating conditions. Took this image from my 2020 manual.

This is interesting - I read someone mentioning something similar in another thread. Just checked my Ram app & nowhere on the 150k miles and less does it mention to change transmission fluid. I will double check my manual also when I have time later.

 

[c3k]

A flush may make issues worse. If it involves a pressurized flow into the transmission, I wouldn't do it. Using the transmission's pump to exchange fluid is fine: a flush is not something I'd ever do. (Flush meaning an external pressurized flow pushes into and then out of the transmission.)

Could be a nomenclature thing...

Drain and fill: if you do this (as I do), think that 1/2 the fluid gets swapped. If you do 5 drain and fills, that's (1/2)^5 of old fluid left. Or, 1/2 * 1/2 * 1/2 * 1/2 *1/ 2 or 1/32 of the original. That's about 97% fresh.

ZF says that 100,000 mile fluid swaps create "an acceptable level of failure". I don't know what is acceptable at their corporate level, but my acceptable level is precisely 0%.

 

[wegasque]

Drain and fill: if you do this (as I do), think that 1/2 the fluid gets swapped. If you do 5 drain and fills, that's (1/2)^5 of old fluid left. Or, 1/2 * 1/2 * 1/2 * 1/2 *1/ 2 or 1/32 of the original. That's about 97% fresh.

Dilution is the solution...

 

[SD Rebel]

This is a good ZF8 DIY oil change vdeo, he mentions that most manufacturers who use this transmission don't even mention a service interval while ZF does. In other words, may want to follow ZF's recommendation instead of anything in the owners manual.

Note this is for the 8HP45 transmission, the RAM DT uses the 8HP75. The part numbers for the pan with intergraded filter is not the same as the one in the video. Video is a good example
of what is involved with the transmission service even if you don't plan to DIY.

It also includes a oil analysis at the end of the video based on a 50,000 mile fluid change.

 

[Bpebler]

Thanks for the replies everyone! I will look into all of these tomorrow. Thanks for taking the time! It’s crazy that Ram wouldn’t follow ZF’s recommendations.

 

[SD Rebel]

Thanks for the replies everyone! I will look into all of these tomorrow. Thanks for taking the time! It’s crazy that Ram wouldn’t follow ZF’s recommendations.

Apparently no manufacturer follows ZFs guidelines, or even an interval at all based on that video.

Maybe they don't want your tranny to last too long? Better for them you buy a new vehicle or new parts to keep it running, hmmmm.

 

[Threesuns1]

This is a good ZF8 DIY oil change vdeo, he mentions that most manufacturers who use this transmission don't even mention a service interval while ZF does. In other words, may want to follow ZF's recommendation instead of anything in the owners manual.

Note this is for the 8HP45 transmission, the RAM DT uses the 8HP75. The part numbers for the pan with intergraded filter is not the same as the one in the video. Video is a good example
of what is involved with the transmission service even if you don't plan to DIY.

It also includes a oil analysis at the end of the video based on a 50,000 mile fluid change.

Any ideas on how we shift through the gears, 1-8, before topping off with our rotary selector?

 

[theblet]

Prob have to use the limiter on the steering wheel

 

[J-Cooz]

I plan on having mine changed around 80,000 miles or so. Ram doesn't recommend it, but ZF does. I'm going to go with what zf says. I figure it's cheap insurance. I also tow a lot in the winter.

Sent from my SM-G781W using Tapatalk

 

[HSKR R/T]

I would definitely follow the recommendation of the company that makes the transmission over what Ram says. They are going to know better what is or isn't good for the transmission

 

[OCD Solutions]

Here's an article on Automatic Transmission fluid that pertains to the discussion.
Published in 2005 by Allison Transmission for General Motors

https://www.lube-media.com/wp-content/uploads/2017/11/Lube-Tech040-UNDERSTANDINGHOWTHETRANSMISSIONFLUIDRESPONDSTODAILYOPERATIONSPart1of3etal.pdf