In looking for a high quality fluid for my ZF I've been following a thread on PSN that Rideracelivemx posted about synthetic fluids. It shifts well and I doon't know of any problems with it but I know it could shift smoother. I'd like to get the cheap fluid out and put in something better. Here's where I stand.

I've seen rave review after another about Redline MTL. It's 70w80 gear oil. Seems kind of far from the specified sythetic ATF but if it works then it works. I also see Redline D4 ATF and Redine Synthetic ATF which seem to be much closer to spec for the ZF but I can't find anyone who has used either.

I saw where another guy said the spec he received(from ZF) said to use Castrol Transynd which is a TES-295 approved fluid for the Allison trans. In that case there are several other TES-295 approved fluids like International's Fleetrite Synthetic ATF, Mobil Delvac Synthetic ATF, John Deere HD Syntran, and Volvo's Bulldog Synthetic ATF. Amsoil also says that their Torque-Drive Synthetic ATF is TES-295 compliant but I've read arguments about that.

There's also this Motorkote product one of the members here is pushing but I still am unsure about it.

Any experience with any of these or suggestions on what route to go? I need my ZF to last a long time and shifting smooth would be a nice bonus.

 

id love to vouche and say that MTL works but i havent boughten it yet becuase i plan on rebuilding it in the next few months so ill just deal with the mobile1...even thoe its slowly smoking my syncros!!!! first is going,2nd is getting worse 4th catches on a hot run and 5th is butter still, reverse!?! dont get me started on reverse....its a 1 minute procedure getting into it when its cold

 

Yeah seems like everyone really hates the mobil 1. I can assure you I won't be going with it. Hopefully this thread will go somewhere good!

 

I would think Redline MTL would be fine. I've never had a ZF tranny but MTL has worked very well for me in the past. Depending on the climate in your area.

 

I liked the royal purple I put in my bros mazda 6. Shifted noticably smoother. I know its not a zf but it made a difference there

 

I used Amsoil synthetic in my trans when I first got it. It shifted very good with that. After the rear oil seal went out in it and I was forced to drive it 5 miles or so w/ no fluid I put in Royal Purple once I got it to hold fluid again. It has never shifted the same since, but it still shifts pretty good even after running dry for a few miles. 3rd gear is starting to scratch some, but no big deal. I will be running the Royal Purple in it after I put my cryo'd trans in it. It's way easier to find Royal Purple around here than Amsoil, but I like Amsoil's products equally as well as the Royal Purple stuff I've used.

 

I used the synthetic Redline ATF in my previous truck and it was WAY better than the Mobile 1 that is in my current truck.

 

Redman, try something & let us know, as a tranny man I would be interested, Gigger

 

Not a huge fan of how Royal Purple makes the ZF syncros bind up. I use Castrol SynTorq with great results Amsoil also makes an oil really close to Syn Torq and it is about half the price.

 

i can vouch for royal purple, thats what was in my tranny to begin with and i had zero issues besides my reverse being junk but thats how i got the truck. shifted pretty good, i think RP is expensive thoe..

 

I'm using Royal Purple Synchromax in mine, not ATF. It's been in there a couple years now with no troubles, not much difference in shifting cold vs. hot. As mentioned before, RP is available at a lot of local parts stores.

 

The synchromax is ATF. At least it says so on the bottles of it I just got and it looked like ATF.
YOu have to use synthetic ATF in ANY stick shift behind a powerstroke. NOT gear oil. That's what the owners manual and ZF specify for them. The brand doesn't matter and if anyone says different because one brand worked supposedly better than another then their transmission had problems to begin with. You can't fix messed up synchros with a different brand of ATF.

Some bone head at the Ford dealer put gear oil in mine for some stupid reason right before I bought it and it destroyed the synchros. Don't even try it.

 

So what I've gathered is that a lot of folks like AND use RP and everyone thinks Mobil 1 is crap. Maybe I'll try something new then. There are a lot of places to get hard to find fluids around me so I guess I'll pick one and see what happens.

 

Jacob just pick one & let us know, seriously, Gigger

 

I've had good results with Amsoil ATF. When I switched out my other vehicles. The operating temps that the trans ran at were ALOT lower with the Amsoil ATF.

I'm sure RP would be the same.