Who runs Royal Purple Syncromax in their 3650?

I used Mobil 1 synthetic 75w90 with a bottom of friction modifier.

sorry don't mean to jack the thread, just have question

i was told by several shops. not to use synthetic in my 3650,
instead they said to use. just regular mercon V non synthetic
something about the synthetic being too slippery for my old Synchro's ???

I only run motorcraft engine, trans, and gear oil in my car. I have no issues. In my 98 stang, I ran RP and didnt like it and was wayy over priced..

My experience with Royal Purple is that I noticed that my tranny was running noticeably warmer. I could feel it in the cab around the center console area especially on long drives. I never had any mechanical problems but the increased heat can't be good for the tranny.

Switched to Amsoil and the heat that I felt with Royal Purple in the tranny was gone. Also, you can REALLY feel the difference in how smooth the tranny shifted after switching from RP to Amsoil. It's like butter and the dreaded T-3650 grind does not occur as often with the Amsoil in the tranny.

johnnyt03gt said:

sorry don't mean to jack the thread, just have question

i was told by several shops. not to use synthetic in my 3650,
instead they said to use. just regular mercon V non synthetic
something about the synthetic being too slippery for my old Synchro's ???

Click to expand...

1st. Anyone who says slippery shouldnt be giving you oil advice.
Otherwise, Mercon V itself is a semi-synthetic/synthetic anyways.