Transmission cooler ideas

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Matt69olds

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One step forward, 2 steps back. Combine with the “Might as Well”, means my transmission swap is taking much longer than anticipated. I have had this transmission sitting on a shelf for years, I thought I had gathered all the parts and little things I’d need. HA!

Got my TV cable brackets sorted out. There is a difference in carbureted and throttle body tv cables. That problem #1 solved.

Problem #2: I had to slide the crossmember rearward for the 700 trans. Since my truck is a 81, and the 700 didn’t come out until 82, none of the mounting holes were in the frame. I had the crossmember in and out about a dozen times to mark and drill holes, but it’s in there.

However, sliding the crossmember backwards has the exhaust and crossmember trying to occupy the same space. Normally, this wouldn’t be too big a deal, except I had exhaust put on this truck last year. Now, I’m debating whether to go ahead and put the headers on it now, knowing I’m going to want them eventually, or just having new head pipes made and putting the truck back on the road.

While I’m debating and brainstorming, I thought I’d pick the brains of the members here about transmission coolers. What fits well? What brand? Where and how did you mount it? I won’t use hose clamps and rubber hose, it will either be AN hose or I’ll have real hydraulic hoses made. I also refuse to use those nylon zip strip mounts that go thru the radiator.

So, how about some pics and discussion?
 

1lejohn

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I always use the B+M coolers. I've used both the rubber slip on with clamps and the screw fittings with AN fitting. I have also used the one with a fan mounted to the cooler. The 99 Camaro pictured in my sig. Had coolers for oil, trans, and power steering. The oil and trans were mounted behind the openings on the front fascia. I know some guys put the coolers under their cars. I'm thinking there is plenty of room to mount one on the frame of a square. You might also look into a Deral pan they have cooling tubes on the bottom of the pan air flows through them.
 

fast 99

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Some later models have a bracket mount factory cooler, possibly adapt one or at least use the mounts. Anything you buy will likely be universal. Is there a pick and pull near you?
 

75gmck25

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Long Mfg. Low Pressure Drop (LPD) coolers are stacked plate coolers (same design as B&M) and them come in many sizes. Most have a low temp bypass that automatically lets trans fluid bypass the cooler until the fluid is up to operating temperature.
 

legopnuematic

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On my 76 and 79 I have Hayden 689 coolers. -6an connections, plate and fin design, rated/intended for Class A motorhomes, towing up to 10,000 lbs, 22,000 GVW. Should be plenty for the TH350's.

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Nasty-LSX

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One step forward, 2 steps back. Combine with the “Might as Well”, means my transmission swap is taking much longer than anticipated. I have had this transmission sitting on a shelf for years, I thought I had gathered all the parts and little things I’d need. HA!

Got my TV cable brackets sorted out. There is a difference in carbureted and throttle body tv cables. That problem #1 solved.

Problem #2: I had to slide the crossmember rearward for the 700 trans. Since my truck is a 81, and the 700 didn’t come out until 82, none of the mounting holes were in the frame. I had the crossmember in and out about a dozen times to mark and drill holes, but it’s in there.

However, sliding the crossmember backwards has the exhaust and crossmember trying to occupy the same space. Normally, this wouldn’t be too big a deal, except I had exhaust put on this truck last year. Now, I’m debating whether to go ahead and put the headers on it now, knowing I’m going to want them eventually, or just having new head pipes made and putting the truck back on the road.

While I’m debating and brainstorming, I thought I’d pick the brains of the members here about transmission coolers. What fits well? What brand? Where and how did you mount it? I won’t use hose clamps and rubber hose, it will either be AN hose or I’ll have real hydraulic hoses made. I also refuse to use those nylon zip strip mounts that go thru the radiator.

So, how about some pics and discussion?
You might want to see my video before you spend the cash!!! FF to 1:40

xc_hide_links_from_guests_guests_error_hide_media
 

Rustisbest

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I used a Hayden 679. Mounted to the passenger side on the core support with aluminum angle and threaded inserts. Rubber hose and fuel injection style clamps.
 

idahovette

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On my 76 and 79 I have Hayden 689 coolers. -6an connections, plate and fin design, rated/intended for Class A motorhomes, towing up to 10,000 lbs, 22,000 GVW. Should be plenty for the TH350's.

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Again Lego I really like the Plate!
 

Bextreme04

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Long Mfg. Low Pressure Drop (LPD) coolers are stacked plate coolers (same design as B&M) and them come in many sizes. Most have a low temp bypass that automatically lets trans fluid bypass the cooler until the fluid is up to operating temperature.
Long makes the coolers for B&M. B&M doesn't actually make any coolers themselves, they just take the Long ones and rebrand/jack up the price.
 

RanchWelder

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My build got the Derale:
https://www.summitracing.com/parts/DER-54078
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12.75 in. x 13 in. x 2 in

My 4L80E has larger diameter lines than the 700R4 had, so plumbing through the radiator and using a standard cooler was out. Shrinking the lines means poor circulation.

Had to go stand-a-lone, so the Derale was what seemed to fit the bill.

Used the stock GM auxiliary fan from the K2500 with the bracket cut down a re-drilled a bit shorter.

It got the blades and wires flipped and re-wired as a pull config.

Fit very clean in front of my 21" x 28" OSC Radiator.

I made 2 stainless steel plates with bends at each end, to encase the cooler on both sides.
It comes with 2 tiny pop rivets on each corner, that would never be strong enough to hang from or hold the plates together without added frame. Plan on building a case of some sort to bind everything together.

The plates were 1-1/2" wide and 15" long or so and I notched them so they could get close to the fittings and slide tight over the rivets.
Then I bought 1/4"x20 threaded rods, ready-rods, from the hardware store, with several sets of nuts and washers.

Then I cut the rods so they stuck out the top 6-7 inches and drilled 2 1/4" holes in the top cover of the core support, so they ride just behind the front lip of the inner hood and just in front of the hood latch assembly.

Cut some spare aluminum tubing at a 45 degree angle for the rod that ended up on the rake of the core cover and it sits very clean several inches in front of the radiator and right in front of the small pusher fan. Fittings down so it doesn't hold silt.
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I didn't see anything else for sale in the thicker dimensions than the Derale.


Couldn't find any actual real world advice on a stand alone for the 4L80E in the square body, without A/C for use in severe cold weather?

So it gets manual fans and the best I could for now.

Wish I had watched your entire video before hand Nasty-LSX.

In well over 50 searches on amazon, summit, Jegs, Speedway, the cooler and the bracket kits for the 40 row PKSABB with the fabricated brackets, never once showed up on any of the pages where I searched for a cooler that would work.

I saved dozens of links in the transmission cooler bookmarks file I created with options and the best prices from at least 6 suppliers, for a stand alone option.

Not one page in the links, brings up the PKSABB kits as an option, even in the adds on every searched page. Not one. Evil Energy is all that came up over and over again at amazon.
None of those were wide or thick enough for stand alone.

Guess I got ripped off by Derale?
Or is Derale the only option that is a full 2 inches thick, with 40 cores?
 
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legopnuematic

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225/6, 350 c.i., 350 c.i., 5.9l Cummins

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