Fyi

[Beav]

From the Hayden Trans cooler website FAQ:

Q. Can you over cool the transmission fluid?
A. Transmissions are not highly sensitive to cool operating temperatures. However, in sub-zero (20-30° F) weather conditions transmission fluid can actually gel up in an external cooler and cease to flow, causing damage. Use of the radiator cooler actually helps warm the fluid under these conditions. It is critical in extreme cold conditions to use the original equipment cooler in series with the auxiliary cooler and allow the vehicle to warm up before driving.


Just food for thought

Beav

Originally posted by Beav
From the Hayden Trans cooler website FAQ:

Q. Can you over cool the transmission fluid?
A. Transmissions are not highly sensitive to cool operating temperatures. However, in sub-zero (20-30° F) weather conditions transmission fluid can actually gel up in an external cooler and cease to flow, causing damage. Use of the radiator cooler actually helps warm the fluid under these conditions. It is critical in extreme cold conditions to use the original equipment cooler in series with the auxiliary cooler and allow the vehicle to warm up before driving.


Just food for thought

Beav

Thats exactly the explination I got from the shop that installed my cooler. They sure know their coolers i guess... Wish i could say the same about SVX Trannys.

-Mike

[svxistentialist]

Putting them in series does obviously make sense in this very cold climate context. Most of us being used to overheating trannies, we tend to think of the matrix in the radiator as a cooler. It is in fact a liquid/liquid heat exchanger. When the air temp is v. low, the oil is kept warmed to the temp of the engine coolant in the rad.

However, this does not take into account that all the older SVX radiators, I am talking '92 to '94 here, but correct me please if I am wrong, have a 'turbolator' at the oil inlet. This is meant to cause turbulent flow and increase the efficiency of heat transfer. Unfortunately, it also gets clogged with gunge and debris from the tranny, and reduces flow through the matrix, and so has the opposite effect. Putting an additional cooler in line or in series with one that is causing reduced flow does not seem a sensible option to me.

However, if you run your car in very cold temperatures, you should consider a series setup if installing an extra cooler. But don't connect it in until you have had the agent conduct a flow test after the rad cooler to ensure you have not got a clogged or badly restricted OEM cooler.

Remember, you will get the same low temperature heating effect by fitting the additional[in parallel] cooler sandwiched between the rad and the air-con matrix, plus you will ensure that clogging of the 'turbolator' at some future time will not cook your tranny.

Joe

[Aredubjay]

Originally posted by Beav
From the Hayden Trans cooler website FAQ:

Q. Can you over cool the transmission fluid?
A. Transmissions are not highly sensitive to cool operating temperatures. However, in sub-zero (20-30° F) weather conditions transmission fluid can actually gel up in an external cooler and cease to flow, causing damage. Use of the radiator cooler actually helps warm the fluid under these conditions. It is critical in extreme cold conditions to use the original equipment cooler in series with the auxiliary cooler and allow the vehicle to warm up before driving.


Just food for thought

Beav

I can respect the opinions of a professional in speaking generally, but, (and this is inquisitively, not sarcastically) why "in series" as opposed to "parrallel?" I know that there has been much discussion in this regard over the nearly three years I've been involved with these forums (yahoo & network).

I would think, especially in the SVX's case, that parallel would be the better path to take (in the 92 anyway), with the 92's propensity for clogging up the stock cooler. If you're in series, you risk a "no path" problem if the stock cooler clogs, whereas, in parallel, you at least have a pathway around the clogged stock unit. Some say flow rate is affected by the parallel path, but, others say it is negligible and should not be a detriment.

Just wondering.

[1994SubaruSVX]

is one that i am willing to take. i live in memphis and it is almost never below zero here. in the winter we average around 40 degrees. the problem here is heat and clogging. an extra tranny cooler that runs parallel to stock works for me. i took that a step further and said to hell with the stock cooler. i run b&m only. i simply keep it maintenanced. i have no worries.

My mech also said the same thing, when mine was installed. He also said that the tranny will not shift into 4th untill the tranny fluid gets to temp.