[Val Walkinshaw]

Been down the many hours/days long rabbit hole on this forum about what trans fluid is best.....

3rd gear synchro is shitting the bed at 41k on my 2018 Tremec 6060. Weekend car. Garaged all winter. Never seen snow/salt. 6 track days. Spirited drives in the mountains. Otherwise care is driven normally. I don't use NLS and can count on one hand years ago how many shifts I've accidentally missed. 1-2 shift is fine. 2-3 started grinding occasionally above 4k (4 times) All other gears are fine. In the 300 mile drive home from TN to OH I heard it a total of 3 more times.

Got home and swapped out the OEM fluid (it looked really normal/good). No particulate matter or glitter. Put in Redline D4. Took it for a 5 mile drive and the shifting is 100% worse-grinding all the time I currently have 4 bottles each of RP Synchromax and Tremec Manual Trans fluid. Plan is to swap today. Going on the the Hot Rod Power Tour in 3 weeks and just need to do what's best to nurse this through until I get back and can get her into the shop.

I'm inclined to skip the RP and use the Tremec fluid.


Thoughts?




For Reference
Viscosity Index
RPurple 162
Tremec 167

RPurple @ 40 °C = 39 / @ 100 °C =7.5
Tremec @ 40 °C = 71.6 / @ 100 °C = 12.1

[cadyshac]

I put RP in mine and can't say it's any better or worse than the factory fill. My problem is getting it to go from 1st into 2nd under normal driving. I feel like a previous owner tried to force the issue when the 1st to 4th was engaged at low speed. I am thinking they've bent something? I've installed skip shift to defeat the 1st to 4th but still my problem lingers. I am very cautious letting the clutch out when going into 2nd, I have to make sure it is fully in gear.