Gear pump run off a cordless drill or 3-8 air ratchet that pushes ATF up through the fill plug on sealed transmissions, transfer cases and diffs.
Filling a sealed transmission, a transfer case or a differential from underneath is the job a hand pump makes miserable. The fill hole is on the side of the case, the bottle is below it, and gravity is working against you. The HT-1720 kit solves that with a small gear pump driven by the cordless drill already in your toolbox, or by a 3/8 inch drive air ratchet, so fluid moves from the bottle to the fill port at a steady rate while you watch the plug. It suits DIY owners servicing a 6L80 Silverado or a 6R80 F-150, and shops that want a cheap, fast way to top off diffs and transfer cases without wheeling out an air-powered tank.
Inside the fiberglass-reinforced nylon housing is a pair of meshing gears. Turning the input shaft pulls fluid in through the suction hose and pushes it out through the discharge hose, and flow rises with shaft speed: the listing rates it at 6.3 pints (3 liters) per minute at 1,200 RPM, so a typical four-quart refill takes under two minutes. A strap-on universal adaptor holds the pump against the drill body so it cannot spin, and a fold-away bracket lets you drive it with an air ratchet when you want slower, more controlled flow near the end of a fill. Quick-couple fittings let you change hoses without taking the pump apart. Reverse the hoses and the same pump becomes an extractor that pulls old fluid out of a pan or diff.
The base pump is rated for transmission fluid, gear and differential oil, engine oil, coolant, power steering fluid and brake fluid, and it is not for flammable liquids such as gasoline.
A fast pump does not set the level; the procedure does. On the GM 6L80 there is no dipstick, and GM's owner information describes a special check and fill procedure with the engine running and the fluid at temperature. Fill until fluid weeps from the check port at the right temperature, then install the plug. Our transmission drain and fill guide walks through the general steps, and the 6L80 Camaro fluid change and 6R80 F-150 fluid change guides cover two of the most common sealed units. Remember that the transfer case is a separate system: GM, for example, calls for its own AUTO-TRAK II fluid in its automatic transfer cases, so never assume ATF goes in every hole.
This is a universal service tool. The kit includes the pump, two 8mm x 1m hoses and one 6mm x 1m hose, a 1/4 inch hex to 3/8 inch drive drill adaptor, an assortment of fill-plug adaptors for common domestic and import applications, and a blow-molded case. Fill threads differ between makers, so check that one of the supplied adaptors fits your plug before you drain anything. For units the kit does not cover, a 33-piece ATF fill adapter kit or the Ford 5R55W and 5R55S fill adapter extends coverage, and more service gear is in our tools category.
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Any cordless drill that can hold the 1/4 inch hex to 3/8 inch drive adaptor will work, and the universal strap fits different drill sizes. You can also drive it with a 3/8 inch drive air ratchet using the fold-away bracket.
The kit is rated at 6.3 pints, about 3 liters, per minute at 1,200 RPM. Flow drops at lower speed, which is useful for the last bit of a fill near the check plug.
Yes. The pump handles gear oil and differential fluid as well as ATF. Use the fluid the transfer case or axle is specified for, which is often not ATF, and flush the pump between fluids.
Yes. Swap the suction and discharge hoses and it will pull fluid out of a pan through the drain or fill opening, or out of a reservoir.
The kit has adaptors for common domestic and import fill plugs, but threads vary by maker and model. Check the plug thread first; if none fit, a larger adapter kit attaches to the same hose.
Do not use it with flammable liquids. It is meant for transmission fluid, gear oil, engine oil, coolant, power steering and brake fluid.
