i am not positively sure how this is going on on my truck and I know a couple of you guys have it so I am all ears. Another is which one is the returnline the top line or the bottom line@ the radiator? his going on my 97 Blazer 4.3l

 

The top line is the line you want to use.

 

So the top one is the one that has to be used right is this the one coming from the tranny or going. I noticed that the top one is the hotter one.

 

Are you sure the tope one is the right one Swart why would it run thruogh the b&m cooler and back through the radiator. Is it better to have it run through the radiator first and then the B&M cooler then to the tranny?

 

Well, it depends on where you live. I run mine in the line out from the transmission so that the cooler will take the brunt of the heat away, and then it will go through the radiator and if necessary, it will warm back up to a certain degree. I run mine this way because of the cold temps in the winter, but really it doesn't really change all that much in the summer time. I would only recommend putting it in the return line to the transmission if you are towing A LOT and need the extra heat dissipation of the coolant in the radiator. Seeing as how the integrated trans cooler is on the cold side of the rad, it will take quite a bit of heat out on its own, but the aux cooler will always take out more.

 

Is a tranny cooler only recommended if you pull heavy loads or carry a lot of stuff or shift a lot?

 

I have put a tranny cooler on everything I own since I bought my first car. By reducing the temperature of the tranny fluid, you'll prolong the life of the transmission. Stop and go driving is almost as bad, as far as heat buildup in the tranny is concerned, than towing a heavy load because the torque converter is unlocking frequently.

 

The top line on the radiator is the return line. That is the one you want. You want the tranny fluid to enter the radiator at the bottom, circulate through the radiator, then exit and circulate the auxilary cooler and return to the tranny. That way it will be the coolest when returned to the tranny.

If you run it to the auxiallary cooler first, and then to the tranny, the rad. will actually warm it up before it returns to the tranny.


The number one reason trannies fail is due to heat. Keep it cool and she will last a long time. Let it run hot and you greatly shorten its life span. Keep it cool.

Towing, moutains, dusty roads, and stop/go traffic raise the heat considerable. Those are considered extreme conditions, get a cooler if you drive in any of those conditions daily.

 

Are you sure that the top line is the return? I mean, that's the way I have mine in, but any directions you get with a cooler will give you circumstances to put it before the rad and after the rad in the plumbing of the cooler. And the last directions I had stated was exactly what I reiterated here.

I don't know if this is related to how I have my cooler plumbed or not, but... Today it took about half my drive in to work for my TC to lockup fully (4*F outside). I was running at 60mph @ ~2000rpm. Once fully warmed up, it runs 60mph @ ~1750rpm. That has a rather large impact on fuel mileage. On a warmer day (like this past friday), I never really noticed that the TC wasn't fully locked up. The tranny warmed up basically before I made it out of town... 2-3 minutes vs ~10 minutes...

 

Hope this works.
Link to tranny site