Gernby

I changed over to the Synchromesh fluid last night. I am really happy with it too. I changed the oil while the tranny was hot, so I didn't get to see how it did cold until this morning.

I did a 40~50 mile hard drive, with allot of stop lights, and found that I could only make it grind once. I got the grind into 2nd gear in the first 2 minutes of driving after changing the fluid. I don't know if it was due to the fluid being psuedo-cold, or if it was because I shifted ugly. What I do know is that I was shifting as fast as I could into 2nd gear, to see what the limit was going to be. I couldn't repeat it.

This morning, I was expecting it to be notchy, or difficult, but it was not. Even cold, the tranny shifts better with this fluid than it did with fresh Honda MTF.

The only thing that I am a little concerned about is how well this fluid will pump. Since our tranny has a pressurized lubrication system, this oil may not "squirt" as well as the Honda MTF. I have seen a couple threads about how sensitive the pump is under certain conditions.

marcucci

Chris, can you elaborate on your comment on VI? I'd be interested to see how the quoted numbers compare to, say, standard 5W30 or 10W30 across temperature.

Prolene

I was also going to ask that question as well.

Of the specification tables comparing Mobil 1 with Synchromesh, VI was much higher in the latter compared to 10w-30, but the "viscosity" at 100 deg and above were similar to 10w 30, and thus much lower than 15w-50.

Perhaps someone can find a table wrt Mobil 1 gear oil.

cdelena

Some quotes from reference:

Viscosity index (V.I.) is an empirical, unitless number indicating the effect of temperature change on the kinematic viscosity of an oil. Liquids change viscosity with temperature, becoming less viscous when heated; the higher the V.I. of an oil, the lower its tendency to change viscosity with temperature.

The V.I. of paraffinic oils is inherently high, but is low in naphthenic oils, and even lower in aromatic oils (often below 0). The V.I. of any petroleum oil can be increased by adding a viscosity index improver. High-V.I. lubricants are needed wherever relatively constant viscosity is required at widely varying temperatures.

BTW, I have used the GM product with great luck in Tremec boxes in the past, but it was too heavy in a T5 box. That is why I am very curious about the suitability when cold.. but if it is that good we could always go back the Honda stuff in the fall.

Gernby

Does viscosity relate directly with thickness? If the oil is too thick, it may not flow between items with tight clearances, right? This stuff seems great for the synchros, but how do we know if the oil is penetrating into the bearings?

marcucci

Too heavy in a T5, based on...? Grinding or notchy shifting, what?

Just curious, I have no idea how to compare oils with respect to performance over temperature.

StrangeDaze

Is this Spoon drain plug you have the same one that fits the Integra/Civic? Thanks in advance...

cdelena

[QUOTE]Originally posted by gernby
[B]Does viscosity relate directly with thickness?

Gernby

Based on the definition of V.I., it seems that since Synchromesh has a high V.I., the viscosity should change little whether it is cold or hot. I guess there's not much benefit worrying about it until it gets cold. It was simple enough to change.

Question: I replaced my crush washers with new ones, but I noticed that one side of all my assorted washers is rounded, and the other side is flat. Does it matter which side faces the bolt head? I put the flat side to the bolt head, and the rounded side to the trannsmission housing.

Gernby

I forgot to mention something else I noticed at lunch. I put the top up, so that I could see if the tranny was as noisy as it used to be, and it seems to be much quieter. In fact, I can't hear it at all. Ever since I got the car, I have been annoyed by how much gear noise I could hear over the engine with the top up, but it is quiet as a mouse now!