TH400 Oil cooler Pan

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

v2500burb

Full Access Member
Joined
Jan 24, 2014
Posts
420
Reaction score
7
Location
Charlottesville Virginia
First Name
Jay
Truck Year
1990
Truck Model
v2500
Engine Size
350ci
Cooler is here
Now come more questions:
1. Run in line with radiator?
2. Which line on the th400 is supply (hot fluid needing cooled)
Which is return?


Sent from my iPhone using Tapatalk
 

GTME94

Full Access Member
Joined
Jan 20, 2013
Posts
441
Reaction score
31
Location
Metro Detroit/Holland, MI
First Name
Terry
Truck Year
86
Truck Model
C2500 C6P Camper Special
Engine Size
454/TH400/14bff 3.73
I was also told, cooler first then through the factory cooler in the radiator then back to the trans.

It may seem counter intuitive to potentially heat it back up after the aftermarket cooler but you don't want the trans fluid too cold either.
 

austinado16

Full Access Member
Joined
May 25, 2012
Posts
611
Reaction score
221
Location
Central Coast, CA
First Name
Todd
Truck Year
1990 w/307k miles on the clock
Truck Model
GMC V1500 Suburban SLE
Engine Size
5.7L TBI/4L60/3.42's
How you do this is; Transmission continues to feed the HEAT EXCHANGER in the radiator tank, and then the fluid goes to the external cooler, and then the fluid returns to the transmission.

You do it this way, because the HEAT EXCHANGER in the radiator tank helps the ATF warm up fast, after initial start up. You want that, because "hot" oil performs AND protects at its designed efficiency.

The output line of the transmission goes to the bottom fitting on the HEAT EXCHANGER in the radiator. So you'll leave that fitting alone. You'll disconnect the top fitting on the heat exchanger, and connect the external cooler line to the exchanger's fitting, and then the return line from the cool will connect to that respective (upper) transmission line.

Generally, the external coolers can not be mounted with their fittings facing down, so mount the external cooler with the fittings facing to the side, or facing up. Facing the fittings down creates an air pocket......at least in the stacked plate coolers, which have a bypass row just inboard from the fittings.
 

morrow07

Full Access Member
Joined
Jan 7, 2014
Posts
77
Reaction score
19
Location
San Mateo, Ca
First Name
Ryan
Truck Year
1977 - 1989
Truck Model
Cheyenne - V2500
Engine Size
406 - 350
I ditched the factory by going to a Griffin manual trans radiator. I then went straight to the fin and tube cooler. Along with the deep finned aluminum pan, this tranny never runs hot.

Sent from my SM-G900V using Tapatalk
 

v2500burb

Full Access Member
Joined
Jan 24, 2014
Posts
420
Reaction score
7
Location
Charlottesville Virginia
First Name
Jay
Truck Year
1990
Truck Model
v2500
Engine Size
350ci
Anybody know where to get barbed fittings for trans and radiator?
Previous owner just cut the old lines


Sent from my iPhone using Tapatalk
 

austinado16

Full Access Member
Joined
May 25, 2012
Posts
611
Reaction score
221
Location
Central Coast, CA
First Name
Todd
Truck Year
1990 w/307k miles on the clock
Truck Model
GMC V1500 Suburban SLE
Engine Size
5.7L TBI/4L60/3.42's
You should find them at the hardware store.....a real hardware store, probably not a lowz or home deep hole.
 

v2500burb

Full Access Member
Joined
Jan 24, 2014
Posts
420
Reaction score
7
Location
Charlottesville Virginia
First Name
Jay
Truck Year
1990
Truck Model
v2500
Engine Size
350ci
Do you know size?
I'm assuming it would be brass



Sent from my iPhone using Tapatalk
 

austinado16

Full Access Member
Joined
May 25, 2012
Posts
611
Reaction score
221
Location
Central Coast, CA
First Name
Todd
Truck Year
1990 w/307k miles on the clock
Truck Model
GMC V1500 Suburban SLE
Engine Size
5.7L TBI/4L60/3.42's
I believe how the transmission line connects AND seals, is via "flare" fitting, so you'd be after that style. Maybe 1/4" flare?

So the radiator would get a fitting with the barb, and it would have male threads. The transmission line would get a fitting with a barb, and female flare.........if that makes sense. Both will be brass, or at least mine are.

Here's a photo that shows the fittings, if that'll help:
You must be registered for see images attach
 
Last edited:

v2500burb

Full Access Member
Joined
Jan 24, 2014
Posts
420
Reaction score
7
Location
Charlottesville Virginia
First Name
Jay
Truck Year
1990
Truck Model
v2500
Engine Size
350ci
So the fittings that come with that kit are what I would need for transmission and radiator??


Sent from my iPhone using Tapatalk
 

austinado16

Full Access Member
Joined
May 25, 2012
Posts
611
Reaction score
221
Location
Central Coast, CA
First Name
Todd
Truck Year
1990 w/307k miles on the clock
Truck Model
GMC V1500 Suburban SLE
Engine Size
5.7L TBI/4L60/3.42's
I believe it's the 2 on the right that wind up being correct for our systems. The 2 on the left fit a different style/size connection.

Sorry I can't give better details. It's been quite a few years since I did my install, and because I purchased the kit in that photo, I didn't have to shop for fittings. I just used what came with the Super Cooler.
 

Latest posts

Forum statistics

Threads
42,173
Posts
910,622
Members
33,669
Latest member
dbarham78
Top