Finally got off my duff and decided to replace my leaky gasket on the TH400. Anyone have lube recomendations? or are they all the same? Just curious.

 

H E L L O A N Y B O D Y O U T T H E R E ???

You know I wouldnt have asked this question on any other web site, but with the forum being what it is, I figured I would get at least 20 different opinions on the brand of tranny fluid being used these days. Oh well, I take credit for either asking the most stupid question of the year or I have finally stumped the forum. :D

 

I just had my Vette at the RX and had the tranny flushed and filled with REDLINE transmission fluid. Seems that the turbo 350 with shift-kit likes this change. The shifts are even more crisp than before. I haven't put many miles on it yet......but the snap in the shifting puts a :D on my face.

Rick :cool:

 

I'll share with you my limited knowledge of transmission fluids. Gov't legislation states that all ATF must be compatible with auto transmissions. Because of these guidlines/standards, all (even cheap) ATF is 'satisfactory'. Steve from Bow Tie Overdrives personal theory is that changing the trans fluid often is far more important than the kind of fluid used. And if you buy the cheap stuff, you are much more likely to change it promptly than if you spend $100+ on the nice stuff. That said, there are a couple characteristics of different ATFs.

There are organic and synthetic. The main advantage of the synthetic fluids is heat tolerance. The number one killer of auto transmissions is heat. I believe what happens is that the fluid, when exposed to heat, degrades it's lubricating qualities. This is done to matter of degree BTW, it's not like if the fluid reaches 300 degrees it's BAD and if it only hits 299 it's GOOD, you know? The hotter it gets and the more time it spends hot will determine how bad it is, so you can guess based on your driving style how often to change it (and whatt kind to use). Anyways, if you feel your transmission fluid lives under stressful conditions, you may want to consider synthetic. The difference in heat tolerance is quite significant.

Another property of various ATFs is the 'friction coefficient', or how 'slippery' it is. I don't think an actual "friction coefficient" in the physics sense applies to ATF, but same theory. Traditional ATF allows for more slip than racing (like B&M Trick Shift, Redline) fluids. Your trans is of course better off with less slip as the clutches will live longer, and your shifts will be firmer/faster. Ford's brand of transmission fluid is "less slippery", and I've heard people mention that it may be the same/similar to Trick Shift, although I have no idea how true that is.

Regardless of what fluid you use, if you think that your transmission fluid lives in a stressful environment (climate, driving style, power would dictate this), then you should be running a transmission cooler. The best style of cooler is a "stacked plate" style, as opposed to a tube-and-fin style. Some stacked plate coolers are "LPD" (Low Pressure Differential I believe), which is a feature that allows the trans fluid, when thick and cold, to bypass the cooling plates, and return to the transmission. This allows for faster warm ups, as driving with cold trans fluid is not good for the transmission. This is another reason (aside from being nice to your motor) why you should take it easy driving until your car gets warmed up. Stacked plate coolers are a bit more expensive than tube and fin style, but they cool better and are FAR more durable. Well worth the money.

I hope this information has been helpful, and if anyone has anything to add or correct, I'd like to hear it.

Rob

 

Thanks guys. Just proves once again how good this forum really is. robzr: great info, thanks! Costco has a great price on a case of Mobil, so I'm going with that.

 

Mobil1 synthetic ATF

 

How loose is your tranny? I used to run Ford ATF because of the higher boiling point and extra friction. It's just what all the things like Trick shift etc. are made out of. In a shift kitted TH it really works good. The only down side is everything behind the tranny takes the jolt. Extra friction wares things out. but it's a small price to pay for fun!

 

Tranny is nice and tight. Had no problems other than the leak on the garage floor. Gasket looked good. Going to check out the seals next.

 

Holy cow, you're actually working on it? :D :D

I think the mobil 1 synthetic is a good choice.

 

What I was asking is: Does it bang the gears like a shift kitted trnny or is it a power slide? I always had kitted and they lost something so you increased the grab.

 

Steve: I AM actually working on my car. Can you believe it?

Gkull: I do have a shift kit. Its set up for street not strip.

 

Amsoil synthetic trans fluid.