Synthetic oil to replace tranny fluid?

[Race94]

I've been told to put in 3 quarts of 20w50 synthetic motor oil and it will make my tranny shift better at higher RPM's, anyone done this??

 

[-GSX-Falcon]

I have never heard of anyone putting motor oil into the tranny. Thats why they make "Transmission fluid" if you could just put oil in there, there would be no need for tranny fluid.

 

[Pearl90TSI]

Theres alot of cars that call for 10w-30 motor oil for the manual transmission. I am assuming you are talking about putting it in a 5-Speed, I say go for it, see how it does.

 

[sc2_ct]

In my Saturn 5speed I am running 5w30 Royal Purple instead of the recommend ATF since Saturns are prone to oil starvation at the differential pin at high RPMs (I'm on tranny number 4), and since the switch to the synthetic motor oil the tranny shifts cleaner, and it's held a number of burnouts and high-rpm hijinks that were killing the others. I can't say how well it will work on a DSM tranny since I haven't tried it (I've still got a slushbox in my TSi), but the real thing to check would be whether the synchros use a brass mesh (which could be damaged by a higher sulpher content present in oil that isn't present in ATF).

Another option would be to use something like Synchromax ATF, which could help some. As for the viscosity that was recommended, 20w50 is pretty thick for a transmission -- sure, it will absorb some of the shock from hard shifts and cut down on vibrations, but it will cause a lot of parasitic drag from the windage (the gears splashing through it). What is the factory-recommended fluid for DSM 5speeds anyway???

Either way, I am a fan of synthetic lubricants because they have better surface adhesion and don't fly off of moving parts as easily. I tore down an engine that threw a connecting rod through the engine block, and when I picked up the rod fragments, where it happened, they were still slick (the engine failure was due to a friend who felt he was too good for rev limiters, not by the fluid -- ain't long rod/stroke ratios a bi***? ).

 

[95ESI]

Srry im a newb to to dsm's and tha little connection for my speedometer was missing when i got tha car (tha wire its still there just someone unsrewed tha little thig that goes on tha tranny) and it has been leakin fluid form there and im guesing its preatty dry now since i drove it form fl to nj ........and now i want to put more fluid in and i went to NAPA and tha guy told me look at my owners manual but it doesent say there whta kinda fluid to put in it can anyone tell me what tha "recomended" fluid for a 5 speed tranny on a 95 ESI is?

 

[paranoidTSi]

To smooth out your transmission use Synchroshift or Synchromesh, these are products that have been shown to smooth out your shifting.

I don't recommend motor oil for the simple fact that our cars call for gear lube NOT motor oil. The Gear lube needed is 75W-90 or 75W-85.

 

[Defiant]

Pennzoil Synchromesh.

 

[98RedGs]

Pennzoil Synchromesh.

Definately.