usar17
Full Access Member
- Joined
- May 3, 2012
- Posts
- 596
- Reaction score
- 17
- Location
- PA
- First Name
- Shawn
- Truck Year
- 1985/87
- Truck Model
- K20 Silverado
- Engine Size
- TBI350/700r4/NP208
After much frustration, research, and ordering wrong parts I've finally got the right combination for an easy install. I thought I'd share this information since I was unable to find it ALL in 1 thread here. These are part links to Summit Racing, but you can buy them anywhere you'd like 
Adding an Aux Cooler to a Stock Setup:
- Unhook upper trans cooling line into radiator. This is the return line
- Insert 1/2" -20 Inverted flare male thread to -6 AN adapter into the Radiator port ($6)
- Attach 1/2" -20 Inverted Flare Female thread to -6 AN adapter onto the trans return line ($13)
- I purchased a 6' section of stainless steel -6 AN Hose ($27) for my job. 3' for each line was enough. You buy what you need depending on mounting location.
- Cut your AN Hose to the appropriate lengths. Wrapping them in duct tape and cutting with a cutoff wheel works best.
- Attach the -6 AN Female thread Fittings to the 2 hoses. I used 4 straight fittings. ($7/each) You can get multiple different angles of these ends. Some people prefer the 45 or 90 degree ones.
- I highly recommend buying a cooler with -6 AN fittings to make this easiest. I bought a Derale 7.6" x 13.5" Coolerfor $39. This is a side in/out tube and fin style.
- Mount the Cooler using metals straps (I had some laying around the garage)
- connect all the hoses and you're done. Derale suggests routing the Radiator out to the upper inlet of the Aux cooler. then the lower to your return line
- get your transmission up to temp and add the appropriate additional ATF fluid to compensate for the added cooler.
Completely re-doing your Transmission cooling lines and adding aux system:
- Remove the Hard lines between your trans and radiator. Remove the adapters on your transmission.
- Insert 2 1/4 NPSM to -6 AN fittings into the Transmission cooler ports ($16 for pair)
- Insert 2 1/2" -20 Inverted flare male thread to -6 AN adapters into the Radiator ports ($6/each)
- Mount Aux Trans Cooler in desired location. ($39)
- Measure out and cut your -6 AN Stainless Steel hose for the following 3 sections: Trans outlet -> Lower Radiator Inlet, Upper Radiator Outlet -> Upper Aux Cooler Inlet, Lower Aux Outlet -> Trans Inlet.
- Attached appropriate -6 AN fittings to the hoses. EI straights, 45s, or 90s.
- Add a "little" extra ATF fluid then get transmission to operating temp. Add ATF till at appropriate level.
Adding an Aux Cooler to a Stock Setup:
- Unhook upper trans cooling line into radiator. This is the return line
- Insert 1/2" -20 Inverted flare male thread to -6 AN adapter into the Radiator port ($6)
- Attach 1/2" -20 Inverted Flare Female thread to -6 AN adapter onto the trans return line ($13)
- I purchased a 6' section of stainless steel -6 AN Hose ($27) for my job. 3' for each line was enough. You buy what you need depending on mounting location.
- Cut your AN Hose to the appropriate lengths. Wrapping them in duct tape and cutting with a cutoff wheel works best.
- Attach the -6 AN Female thread Fittings to the 2 hoses. I used 4 straight fittings. ($7/each) You can get multiple different angles of these ends. Some people prefer the 45 or 90 degree ones.
- I highly recommend buying a cooler with -6 AN fittings to make this easiest. I bought a Derale 7.6" x 13.5" Coolerfor $39. This is a side in/out tube and fin style.
- Mount the Cooler using metals straps (I had some laying around the garage)
- connect all the hoses and you're done. Derale suggests routing the Radiator out to the upper inlet of the Aux cooler. then the lower to your return line
- get your transmission up to temp and add the appropriate additional ATF fluid to compensate for the added cooler.
Completely re-doing your Transmission cooling lines and adding aux system:
- Remove the Hard lines between your trans and radiator. Remove the adapters on your transmission.
- Insert 2 1/4 NPSM to -6 AN fittings into the Transmission cooler ports ($16 for pair)
- Insert 2 1/2" -20 Inverted flare male thread to -6 AN adapters into the Radiator ports ($6/each)
- Mount Aux Trans Cooler in desired location. ($39)
- Measure out and cut your -6 AN Stainless Steel hose for the following 3 sections: Trans outlet -> Lower Radiator Inlet, Upper Radiator Outlet -> Upper Aux Cooler Inlet, Lower Aux Outlet -> Trans Inlet.
- Attached appropriate -6 AN fittings to the hoses. EI straights, 45s, or 90s.
- Add a "little" extra ATF fluid then get transmission to operating temp. Add ATF till at appropriate level.
