ZF8 50K Mile Transmission Service -- DIY How-To Instructions

[grimmjeeper]

You just do a drain and fill as opposed to a flush and fill, correct? Any data on how much fluid is captive in places like the torque converter that doesn't get replaced?

Are you going to try a flush and fill at some point?

Sponsored

 

[CarbonSteel]

You just do a drain and fills as opposed to a flush and fill, correct? Any data on how much fluid is captive in places like the torque converter that doesn't get replaced?

Are you going to try a flush and fill at some point?

I have done 3 drain and fills (including changing the filter each time) and am calling it good based upon the reduction of wear metals--in total I have ran 15 QTs through it. I have not found any data which indicates the total amount of fluid in the transmission, but that would be a good thing to know.

No plans to do a flush and fill because there was only 1 dealer in the area who could do it, but they did not seem to understand how the ZF8 works with regards to the temperature controlled systems inside. I would also be concerned about overpressure so I nixed the idea of the dealer doing it.

 

[QwikKotaTx]

You just do a drain and fill as opposed to a flush and fill, correct? Any data on how much fluid is captive in places like the torque converter that doesn't get replaced?

Are you going to try a flush and fill at some point?

Most people have gone away from flushing transmissions as that can break loose deposits or friction material and cause other issues. I typically do drain and fills and have had good luck on modern sealed transmissions. Most torque converters can hold a few quarts so it takes a few drains to get everything and even then new mixes with old fluid. I wouldn't overthink it too much.

My Ram has a similar ZF transmission and I was hoping to be able to draw out some fluid with a small electric pump and refill with the same amount plus a small addition of what might be stuck in the pump and hoses. We shall see.

 

[grimmjeeper]

I have done 3 drain and fills (including changing the filter each time) and am calling it good based upon the reduction of wear metals--in total I have ran 15 QTs through it. I have not found any data which indicates the total amount of fluid in the transmission, but that would be a good thing to know.

No plans to do a flush and fill because there was only 1 dealer in the area who could do it, but they did not seem to understand how the ZF8 works with regards to the temperature controlled systems inside. I would also be concerned about overpressure so I nixed the idea of the dealer doing it.

Fair enough. Would be interesting to know the data points but it doesn't sound like it's easy to come by.

 

[GATORB8]

I have done 3 drain and fills (including changing the filter each time) and am calling it good based upon the reduction of wear metals--in total I have ran 15 QTs through it. I have not found any data which indicates the total amount of fluid in the transmission, but that would be a good thing to know.

No plans to do a flush and fill because there was only 1 dealer in the area who could do it, but they did not seem to understand how the ZF8 works with regards to the temperature controlled systems inside. I would also be concerned about overpressure so I nixed the idea of the dealer doing it.

AllDataDIY has 9.5 qts in the HP 50 and 8.9 qts in the HP75

 

[CarbonSteel]

AllDataDIY has 9.5 qts in the HP 50 and 8.9 qts in the HP75

Nice; so changing over 50% of the fluid with each dump and refill.

@grimmjeeper ^^^^

 

[gsbrockman]

Nice; so changing over 50% of the fluid with each dump and refill.

@grimmjeeper ^^^^

You may enjoy this thread....

https://www.cumminsforum.com/thread...kills-better-than-mine.1729865/#post-19823681

 

[CarbonSteel]

You may enjoy this thread....

https://www.cumminsforum.com/thread...kills-better-than-mine.1729865/#post-19823681

Nice; following the regime in that post, I have about 10% old fluid remaining after 3 fluid changes:

 

[lashlee]

I'll be doing this at the next oil change. I bought one of the PPE pans so I'll get a little more capacity to go along with the added benefit of the bigger heatsink. Thanks for @CarbonSteel for all of the great information!

 

[CarbonSteel]

I'll be doing this at the next oil change. I bought one of the PPE pans so I'll get a little more capacity to go along with the added benefit of the bigger heatsink. Thanks for @CarbonSteel for all of the great information!

Anytime!

With regards to your PPE, if you have a 3.6L, be sure to check and see if you need to trim the fins down where the exhaust crosses over the pan. If a 2.0T, no worries.

 

[lashlee]

Fortunately it's going on a 2.0 so it should be a simple swap!

 

[The Chad]

I'm guessing if the vehicle still has warranty the Stealership will call the filter into question. Anybody have a pan using the stock filter? Just asking because I like the ease of draining. I'd even like a funmoto or femco style drain. On my volvo XC 90 I do this every 4th oil change.

 

[CarbonSteel]

I'm guessing if the vehicle still has warranty the Stealership will call the filter into question. Anybody have a pan using the stock filter? Just asking because I like the ease of draining. I'd even like a funmoto or femco style drain. On my volvo XC 90 I do this every 4th oil change.

Not that I have found, in fact the PPE is the only aftermarket model I have seen at all. If warranty is a concern, I would keep it stock otherwise the dealership could call the pan into question too.

It's not a difficult job to drop the pan for a drain and fill especially since the gasket is reusable.

 

[The Chad]

Not that I have found, in fact the PPE is the only aftermarket model I have seen at all. If warranty is a concern, I would keep it stick otherwise the dealership could call the pan into question too.

It's not a difficult job to drop the pan for a drain and fill especially since the gasket is reusable.

Roger that. Does it look like you can weld in a bung for drainage on the stock pan? I imagine either the filter will be in the way or it won't drain much of the fluid.


I have found with my volvo it was pretty easy to drain cold and add back in the measured amount. After doing that every other oil change it got to a point the ATF was looking clean. They also had a fill for life Aisin "Toyota" transmission.

 

[CarbonSteel]

Roger that. Does it look like you can weld in a bung for drainage on the stock pan? I imagine either the filter will be in the way or it won't drain much of the fluid.


I have found with my volvo it was pretty easy to drain cold and add back in the measured amount. After doing that every other oil change it got to a point the ATF was looking clean. They also had a fill for life Aisin "Toyota" transmission.

You could and it would drain nearly everything, but there are magnets you will want to clean so the pan would need to be dropped to do that. I bought one to install, but decided against it.

The fluid for these transmissions is about $20 per quart so it is about $100 each change. After 3 changes, about 15% of the old fluid remains so I am calling that a sweet spot as there is a point of diminishing returns and I'm not sure what you would gain by doing 4 or 5 changes.

At 3 changes at less than 60K, I am far ahead of the "lifetime fill" curve.

Sponsored