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I just changed out the DMF and clutch to a SMF and it is quite a bit easier on the leg when shifting. I am having a hard time adjusting to the gear lash noise that now is "standard" with the SMF. Is there one trans fluid that helps quite the gear lash sound better than others. I realize it will not go away entirely but anything helps. If you have some thoughts - I'm all ears. Thanks in advance.
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ATF, I used plain ol' Walmart special labeled 'Automatic Transmission Fluid' that states it takes the place of Dexron III and Mercon. Whatever it means it was fine and I use it in many vehicles. I ran it in my ZF to break in the new clutch then went to Redline D4.
Consensus here is to use one extra quart to help with noise. FIll all from the top as it makes life easier.
I have a ZF6 in my SD, but the fluid use is nearly the same, below are my thoughts.
I started with...
Amsoil Signature Series ATF. It was good, but still had some gear roll over noise.
then...
Redline MTL. It was good, but too "notchy" for my liking.
then...
Redline High Temp ATF (30204) and have been using that for 10's of thousands of miles towing heavy long distance/cross country.
I have a good friend that works at ZF Transmissions in Gray Court, SC and spoke to him a bit about the fluid choices I had in front of me. I am satisfied with the outcome of my choice.
The gear rollover is gone, the cold and hot shifting is nice and smooth. Hit Man X is right when he mentioned the filling of a bit extra from the top. The ZF6 calls for 5.7 quarts and I use 6 quarts from the top and done.
I picked up a gallon of Amsoil SAE 50 long life synthetic ATF which the semi guys use. I'll change out the fluid next week and see if there is any noticible difference in the sound. I'll repoert back with results. BTW this atf is said to hold up for 500k miles.
Please do update the thread. I would like to have another alternative to the Redline High Temp ATF in the event they change the formula. I know that I didn't care for the Amsoil Signature ATF, but that is a different product than you have on hand.
I decided to use Royal Purple in the tired ZF5-42 and overfilled. Shifts fine warm and cold. Improved the cold clunk to more of a brief c-h-i-n-k for the first couple miles. Significantly reduced gear noise (and a new insulator pad helped here as well). Overall it seems like the stuff is doing its job.
For fun, I added a pair of FastCoolers and had them treated with a heat shedding ceramic coating.
Mods: why is c-h-i-n-k (without the dashes) a dirty word? Seriously?
HI Guys,
Trans fluid update.
I filled the trans with the Amsoil SAE 50 long life and I say I noticed approximately a 50% reduction in the noise from the gear roll over. Another benefit is that the trans shifts much more smoothly. Amsoil has got my recommendation.
I decided to use Royal Purple in the tired ZF5-42 and overfilled. Shifts fine warm and cold. Improved the cold clunk to more of a brief c-h-i-n-k for the first couple miles. Significantly reduced gear noise (and a new insulator pad helped here as well). Overall it seems like the stuff is doing its job.
For fun, I added a pair of FastCoolers and had them treated with a heat shedding ceramic coating.
Mods: why is c-h-i-n-k (without the dashes) a dirty word? Seriously?
HI Guys,
Trans fluid update.
I filled the trans with the Amsoil SAE 50 long life and I say I noticed approximately a 50% reduction in the noise from the gear roll over. Another benefit is that the trans shifts much more smoothly. Amsoil has got my recommendation.
Outstanding news! It is always nice to see someone have success with a product they researched and paid good money for.
Thanks for the update and we hope it continues to serve you well.
Time will tell. I'm planning 2 coast to coast trips in 2022. One at the end of March and then again in June. I anticipate 15-16K will be added to the clock.
I like the theory of them. Install was straight-forward, so that was nice. And it gave an excuse to clean and paint the PTO covers.
In reality, I do not have temperature measurements before installing the FastCoolers, so have no actual idea if they help. I did install a temperature sending unit in one of the coolers and one day will route a wire to the Edge mostly for the fun of feeding the data-junkie in me.
If anything, the coolers allow for more fluid capacity while also cooling that additional fluid (at least that is the theory). I do need to wrap a section of exhaust pipe as it comes within about 3" of the passenger side cooler.