Vacuum-only MityVac hand pump for the Sonnax valve-body vacuum test, checking vacuum modulators, and pulling ATF. Reaches 25 in-Hg with gauge and adapters.
If you are chasing late, harsh shifts on a TH350 or TH400, fluid disappearing into the engine through a modulator, or a valve body circuit you suspect is leaking, a hand vacuum pump with a gauge answers the question in minutes. The Mityvac MV8000 Automotive Test and Bleed Kit is built around the MV8010 Selectline pump, which carries a gauge reading inches of mercury and kPa, so you get a number instead of a guess.
Vacuum testing works by sealing off a passage and pulling air through whatever clearance is there. A tight fit restricts airflow and holds vacuum; a worn bore, a torn diaphragm or a leaking seal lets it bleed down. Sonnax describes the principle well: a perfect seal reads about 29.9 inches of mercury at sea level, a very good valve circuit may approach 22 to 23 inches, and a badly worn bore can read as low as 8. The MV8010 develops and holds up to 25 inches of mercury and moves about 1 cubic inch (16 cc) per stroke, which is enough to see that difference on small circuits and components.
For a modulator complaint, warm the engine, pull the hose and look for ATF inside it, then connect the pump to the modulator nipple and pump to around 20 inches. A good diaphragm holds steady. Our TH350 common problems guide walks through the full modulator diagnosis, and the TH350 valve body testing guide covers what to check if the modulator passes. If you also want to read engine vacuum at the modulator line with the engine running, the OTC 5613 vacuum and pressure gauge kit does that job.
On the bench, use the pump to isolate a single passage at a time. Sonnax's 4L60-E pump cover article shows the technique: put the test tip on one end of an oil passage and plug the other end with a finger, so only that circuit is being measured. For production valve body testing, Sonnax recommends a test stand with a 3 cfm powered pump, and you set your own pass and fail numbers for your setup. Treat this hand pump as the quick check that tells you where to look, then compare readings against the known wear areas in our 4L60E valve body wear guide.
According to Mityvac's product sheet, the MV8000 includes the MV8010 pump with gauge, a 4-1/2 oz reservoir jar with fluid transfer and storage lid, two 2 ft lengths of 1/4 in ID hose, a rubber cup adapter, two universal bleed screw adapters, a vacuum T adapter, automotive test and bleed adapters and a user manual. The gauge is a gearless diaphragm type on a pinned mount that rotates 360 degrees, and the pump has a one-finger vacuum release and is field serviceable with repair kits.
This is a vacuum pump. It does not build pressure, so it will not air-check clutch pistons or pressure-test a cooler. If you need both, look at the Mityvac MV8500 vacuum and pressure kit. Altitude also lowers the maximum reading, so compare readings taken in the same shop. If the modulator fails, a replacement such as the adjustable TH350 and TH400 modulator lets you set shift firmness after install.
| Pump model | MV8010 Selectline hand vacuum pump |
| Maximum vacuum | 25 in-Hg (85 kPa) at sea level |
| Function | Vacuum only (does not generate pressure) |
| Gauge | Gearless diaphragm vacuum gauge |
| Reservoir | 4.5 oz fluid reservoir |
| Included | MV8010 pump, 4 tapered adapters, tubing, bleed/diagnostic fittings |
Yes. Connect it to the modulator nipple, pull vacuum and watch the gauge. A good diaphragm holds; one that leaks down, or a hose with ATF in it, means the modulator has ruptured.
It is good for quick spot checks of individual passages. Sonnax recommends a test stand with a 3 cfm powered pump for production testing, with pass and fail numbers set for your own equipment.
No. The MV8010 in this kit is vacuum only, up to 25 inches of mercury. For pressure testing, choose a vacuum and pressure pump such as the MV8500 kit.
For small amounts, yes, using the 4-1/2 oz reservoir jar. For a pan's worth of fluid, a larger fluid evacuator is the right tool.
No. The 4L60E uses an electronic pressure control solenoid instead. On that unit the pump is useful on the bench for checking valve body and pump cover circuits.
