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827 Review
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Review on Hayden Automotive 397 Transmission Fitting by Colton Scheehl

Revainrating 5 out of 5

Fits Trans Flush on NNBS Chevy/GMC Trucks

Replace the coolant line on the upper left side of the radiator (on the left side when looking at the car grille). Use 3/8" ID clear hoses. Start the engine (in park position) and allow the coolant to drain out for about 10 seconds. Describe later. Turn off the car. Refill the transmission. Repeat. You may also run the engine until bubbles appear in the lines, stop the engine, remove the sump and prevent the liquid from splashing all over your face (I might as well leave the drain plug on for the kill) Now don't do that, which a lot of people do after a fluid change and don't assume that after all that effort the dipstick will be fine the first time. The fluid will be fizzy and/or not fully fill the torque converter yet. That's why many people believe that their transmission slips after one of those fluid changes, but don't realize they didn't fill it all the way up with heaps of fluid - like 3 gallons You will need at least 4 gallons to pump to replace all the fluid with real ones and be able to completely fill the transmission. To read the dipstick correctly, you need to fill it up, test it, drive the car in different gears, maybe even drive it back and forth a few meters, and then test again. Do this several times. Then when you get back home or at your first destination, check again. If you notice slippage after this replacement, it may well be that you didn't add enough liquid. The dipstick lies after such an invasive replacement, especially if you don't measure what you take out and replace with the same one. . How do I know? Because I've helped a couple of DIYers who were panicking and thinking their transmission failed after a swap (because you hear it "happens all the time"), and it turns out they're running out of fluid just never checked on the first try. Luckily nobody destroyed anything because they didn't drive very far. To be smart. Measure what you take out.

Pros
  • Great for small homes
Cons
  • Questionable purchase for seniors