Questions about ZF 8 transmission fluid change

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Garth Schindel

Junior Member
Joined
Sep 10, 2019
Posts
6
Reaction score
2
Location
Didsbury
Ram Year
2014
Engine
5.7 Hemi
Hi
I've read and watched lots but I still have a couple of questions.

Do I drain the fluid when its cool or when its between the 30-50C (86-122F)? One video https://www.youtube.com/watch?v=kXK...Ds9wMi6TZg&start_radio=1&rv=kXKhZievmSI&t=924
said to drain it when its below operating temp but I thought I also read to heat it up first. Wouldn't you get more out if its warm? Once comment in the video said to drain and then run the engine to get the oil out of the cooler - this sort of sounds reasonable - has anyone tried this?

This video https://www.youtube.com/watch?v=BPkCUfqi-gE talks about how to make sure you have the tranny full to do the regular fill procedure then drive the vehicle until its hot, let it cool and then do the fill check procedure again. This is to make sure the tranny cooler was full too. Needed?

The last thing I'm questioning is how to do the rev to 2000 - is this in park or neutral? Does it matter?

Thanks for the help.
 

MRFREEZE57

Senior Member
Joined
Nov 18, 2019
Posts
466
Reaction score
627
Location
pacific northwest
Ram Year
2016
Engine
5.7 hemi
If I remember correct I ran mine up to temp then let it drain for about 1 hour, then make sure you raise the rear end up to get the tranny level before refilling.
 
OP
OP
G

Garth Schindel

Junior Member
Joined
Sep 10, 2019
Posts
6
Reaction score
2
Location
Didsbury
Ram Year
2014
Engine
5.7 Hemi
I had planned on warming it up before draining but the one video specifically said to drain it cooler than operating temp. He seemed to know what he was talking about. Would doing this keep the fluid out of the cooler so more drains out?
 

PaleFlyer

Senior Member
Joined
Jan 1, 2022
Posts
429
Reaction score
235
Location
Charlotte NC
Ram Year
2018
Engine
Hemi 5.7
I had planned on warming it up before draining but the one video specifically said to drain it cooler than operating temp. He seemed to know what he was talking about. Would doing this keep the fluid out of the cooler so more drains out?
Warm it up some so it flows better, but not to warm, or it's too hot to work with.

As far as drain off what you can, then run the engine... I'm not a mechanic, but I would NEVER do that personally.
 
OP
OP
G

Garth Schindel

Junior Member
Joined
Sep 10, 2019
Posts
6
Reaction score
2
Location
Didsbury
Ram Year
2014
Engine
5.7 Hemi
Thanks. Warm enough to flow makes sense. Keeping it below the temp where it gets into the cooler can’t hurt.

No I won’t run it with the pan off. Even FZ says not to do that that in big bold letters.

After a pan change, Do you believe in changing just the fluid a couple of times to get make it more pure? / less old stuff.
 

MRFREEZE57

Senior Member
Joined
Nov 18, 2019
Posts
466
Reaction score
627
Location
pacific northwest
Ram Year
2016
Engine
5.7 hemi
Thanks. Warm enough to flow makes sense. Keeping it below the temp where it gets into the cooler can’t hurt.

No I won’t run it with the pan off. Even FZ says not to do that that in big bold letters.

After a pan change, Do you believe in changing just the fluid a couple of times to get make it more pure? / less old stuff.
I drained my fluid 3 times total, about 200 miles apart to get a good flush, used Redline D6 but many have said had good results with Valvoline Maxlife.
My advise, go with a PPE pan for replacement, the drain is much easier accessible and not right under the exhaust cross over and it has a replaceable filter. They run about $275 but are well worth the extra cost.
 
Top