How to: factory auxiliary trans cooler upgrade

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97K1500Silverado

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I mentioned this on the last page but the TruCool M7B is the exact same unit as the B&M 70266 (even made by the same parent company, Long Mfg) and they're $75 on Amazon.

https://www.amazon.com/Tru-Cool-M7B-ENGINE-OIL-COOLER/dp/B003TQ7WDA

Thanks!

My 97 k1500 came with the smallish stock trans cooler. I Need these adapters?

Legines NPT Bushing 1/2" Male x 3/8" Female Reducing Adapter Hex Head Pipe Fitting 1200psi Temperatures range from -53 to 121 degrees C (-65 to 250 degrees F)(Pack of 5) https://www.amazon.com/dp/B07L4KXPSK/ref=cm_sw_r_cp_api_glt_fabc_KY49TRS7N5S282CNJFMG

Was pulling my 3.5k lb 7x14 enclosed trailer from 3k feet to 7k feet and trans temp hit 230 - 240 for 20mins then cooled down to 200 for remainder of trip. Sender is in the pressure test port on side of 4l60e so it should be reading hotter temps than if it was in the pan correct?

Running full synthetic Valvoline maxlife. I have a TCI deep aluminum pan (got used for $100) which holds an additional 2qts. I noticed this helps keep lower temps a little longer but once the fluid heats up it takes just as long if not longer to cool down as stock pan. TCI Auto 378000 TCI Transmission Pans | Summit Racing

original 4l60e with 211k on it still going strong!

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df2x4

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My 97 k1500 came with the smallish stock trans cooler. I Need these adapters?

Legines NPT Bushing 1/2" Male x 3/8" Female Reducing Adapter Hex Head Pipe Fitting 1200psi Temperatures range from -53 to 121 degrees C (-65 to 250 degrees F)(Pack of 5) https://www.amazon.com/dp/B07L4KXPSK/ref=cm_sw_r_cp_api_glt_fabc_KY49TRS7N5S282CNJFMG

Looks correct to me, but when I did this it was part of a 4L80E swap into a truck that never had an AUX cooler so I used -6 AN lines and fittings with 1/2" NPT to -6 AN adapters. I'm not the one to ask about the factory lines as I've never really messed with them.

Sender is in the pressure test port on side of 4l60e so it should be reading hotter temps than if it was in the pan correct?

Once again I'm no help as I'm not running any aftermarket temp gauges. I'm sure someone else can answer that though.
 

smashdn

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I am thinking of doing this after reading about the trans issues with the 4l60. And truthfully, I have not dug into my 1998 K1500 Suburban to tell you what trans it has. But just looking at what the previous owner has done and not done I am going to assume it has been neglected to an extent.

Now then, I follow the Amazon link and that particular cooler is no longer in stock/available. There is however a Hayden 689 >
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< but the reviews are all over the map.

I used to have a 2001 Jeep Cherokee XJ (square front Cherokee) that I installed a cooler and spin on filter adaptor and filter for. Part and parcel to that I flushed the trans by breaking open a line and flowing it to a clear jug until all the old fluid had been replaced by new cherry red fluid. I know the old wisdom is don't flush if it hasn't been a regular part of maintenance on the vehicle up to a certain mileage but I am inclined to think if the fluid is old and burnt smelling or looking it needs to go.

So, first question, anybody have experience with that Hayden cooler?
Where would I look to see what transmission I have (or are all certain models/packages/years one or the other)?
Anybody bothered to put the filter in-line to help keep the fluid clean? (Also adds a touch more fluid capacity to the system.)

I tow a boat and may occasionally tow a 16' enclosed trailer. Possibly a camper in the future. It is hilly around here but not mountainous. Am putting a little larger than stock wheels and tires on it but no lift planned.
 

Schurkey

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Hayden is a reputable manufacturer, so far as I know and based on my own experiences. If they've offshored to China, I don't know about it.

That cooler seems plenty large enough. Perhaps over-sized.

If I were installing from scratch like you, I'd probably use -6 steel-braid-over-Teflon (PTFE) liner hose and hose ends, connecting the existing trans outlet-to-radiator tube to the hose, to this cooler, this cooler to the inlet of the radiator cooler with similar steel-braid/Teflon hose, and maintaining the existing radiator-to-transmission "return" tube as-is. That way, the radiator heat exchanger will warm the fluid in the winter so it doesn't get over-cooled.

But that's me.

The only thing I strongly suggest, is that you throw the included hose clamps in the scrap-metal can. Those worm-gear disasters will eventually ruin the rubber hose. Find shielded clamps, "Fuel Injection" clamps, or Oetiker clamps in the correct size (Not easy.) In short, you want to protect the hose from crappy clamps. (Best solution: use the flare fittings and steel-braid hose, and avoid clamps altogether.)

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El Tigre

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Teflon/stainless hose tends to run small so I up-sized to AN-08. Only slightly larger than 3/8" ID ,and use for P/S hose also....
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Schurkey

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Define "runs small".

Tubing is measured by outside diameter, which makes it different than pipe which is measured by inside diameter.

Therefore, the flow-path through tubing varies with the wall thickness. Thin-wall tubing has a bigger hole in it. Thick-wall tubing has a smaller hole.

Hose sizes are based on tubing sizes; it's unusual for "dash 06" hose to have a fluid path that's 6/16 or 3/8 diameter, just as you wouldn't find 3/8 tubing that has a 3/8 hole for a fluid path.



It may be the angle the photo is taken at...but it looks like you've got two hoses and a tube running close together. I suggest you secure those items with cushion clamps to prevent them rubbing on each other. If they touch, they'll wear holes in each other. "Steel braided" hoses are like dull hack-saws. Anything they abrade, they'll wear into--other hoses, castings, steel stampings...whatever.
 

El Tigre

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We are not talking about tubing... Hose is measured by ID. When looking at mfg. specs ,teflon/stainless runs the smallest ID of all the different style hoses. At least w/Aeroquip does. Their "socketless" AN-08 is the only one with a 1/2" ID. Other styles are slightly smaller ,with PTFE hose running the smallest. Only slightly larger ID than a Socketless AN-06. Feel free to visit their website ,and/or catalogue to see for yourself.
 

L31MaxExpress

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Figured I would add this here. My Express van has a 4L85E with a factory diameter converter that stalls 2,900 rpm behind a very healthy 383. I have an in-radiator cooler plumbed in ahead of a M7B cooler. Running it hard in 100*F ambient temperatures here are the fluid temperatures measured at the stock sensor in the pan. Pan is a Moroso aluminum with extra capacity. I laugh every time someone tells me I need to ditch the current M7B cooler, bypass the radiator and put a less effective overall 40K in front of my condenser to warm up my ac.

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L31MaxExpress

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Same run, fluid temp vs vehicle speed. I have heard some people claim that additional oil pan capacity only slows down the temperature drop when the load is removed. I have had others claim a 50*F rise when the vehicle stops at a red-light because of the radiator cooler in the loop. I have had yet others claim that the in-radiator cooler will cause the fluid to run at the engine temperature. ALL of these claims easily refutable from solid actual data! The transmission temperature varied only 14*F from the coolest it ran to the hottest it ran. I started this log after driving about 5 miles to fill up with fuel on city streets. Drove 3-4 miles to the highway then hit the road. These values were from close to a 1-hour trip where I encountered stop and go traffic, stop lights, climbing 3 long grades, as well as 3 different WOT merging/passing accelerations.

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