[Huskymaniac]

Originally Posted by NeedForSpeed

If the above statement is your only true objective, you should immediately delete your entire list. You can not be 'sure' of any of it. Items 1,3,5,6 are considered 'performance' mods, usually for those that drive accordingly. Items 2 and 4 are considered reliability/maintenance mods, but not everyone agrees on the cooler or on synthetic You clearly and correctly stated, the list is based on 'what people believe'.

To my knowledge, other than maintenance, none of the six items you listed has ever been proven to add reliability to a ’96 SVX transmission under normal road use. Most items on your final list have been tested sparely, and for relatively few miles, with mixed reviews.

You have taken the biggest step known and observed in increasing transmission reliability in an SVX, namely, driving a post-92 SVX. I believe that nearly everybody agrees on that. These later transmissions, when properly maintained according to Subaru, will easily approach 200,000 miles without failure. In fact, how many here have had a 96-97 transmission fail?

By 96, Subaru engineers had enough years and miles to correct early reliability concerns in the SVX. That is what you risk by making changes to a car you consider a 'daily driver'. I do not believe that any advice given here regarding reliability, other than periodic fluid change, is conclusive.

If you are looking to change the performance of your transmission, the 'safe' question is a different question entirely, with many opposing opinions.

OK, I will grant you that no one can be sure that any of them will work. However, items 1-4 have never been said to cause damage or possibly make the reliability decrease. But you are right in that, in every case, someone will argue that it doesn't help reliability. I guess I am putting up that list as items that have been widely claimed to be beneficial while not harmful. However, item #6 is the most debatable in terms of whether it will help at all. And item #5 is probably the item that will get the most claims as possibly causing more harm that good. In my mind, though, it does increase line pressure but not to the point where the original intent of that resistor is completely removed. Personally, I am planning to do items 1-4 over time.

On the cooler, there is some debate as to its necessity but it is widely believed that the improved FLOW is, in itself, a help for reliability. Whether the cooling capacity really helps is what is debatable. And whether either is needed for a later model SVX is also debatable I suppose. But I don't see how it could hurt with the only possible exception being that it can restrict air flow to the radiator if placed between the condenser and radiator or in front of the condenser. That can raise engine temperatures. Also, if the cooler is too big and the climate too cold, one might never lock up the torque converter and that will cause poor gas mileage. So, for my car, I am thinking of getting a smaller, lower flow resistance cooler. The estimate I came up with for the cooling capacity of the stock cooler was around 2000 GVM. Any cooling above that is a bonus but the main goals are low flow resistance and small size.

The folks at Hayden were kind enough to send me actual data on their Model 676 cooler. For the size, it is quite efficient at cooling and I can estimate the flow resistance from the data they gave me. I compared that with a flex-a-lite 4110 cooler. I calculated the flow resistance from equations for laminar flow. What I don't know is how turbulant the flow is and how much higher the actual flow resistance is. Flex-a-lite has not supplied data per my request. That alone makes me lean toward Hayden.

Here is a summary of the evaluation thus far: