Myth test1 productsEngine Oil & Fluids
Transmission Additive: The Test Results
A head-to-head test of 1 transmission additive options with the measured results for each. See how they ranked and watch the full test video.
Ranked first
Lucas Transmission Fix
Price shown in test: 10 or 12 dollars for a 24 oz bottle
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The measured results
Every number below is read straight from the test. Scroll sideways to see all measurements. Products are listed in the order they finished.
| Product | Evaporative Loss Test | Lubricity Film Strength Test | Cold Flow Test | Lab Analysis Of Product | Lab Analysis Of Baseline Atf | Real World Road Test |
|---|---|---|---|---|---|---|
| 1Lucas Transmission Fix10 or 12 dollars for a 24 oz bottle | 394.62 g to 394 g after 2 hours at around 300 F, a loss of only 0.62 g, described as doing a very good job; for comparison, ACDelco Dexron 6 ATF (the comparison fluid, not the product under test) lost 1.3 g over the same test (430 g to 428.7 g) | described as doing far better than the ATF, with a huge difference between the two on the lubricity tester | at -20 F, cooked Lucas did not begin moving down the oil slide until about 2 minutes after both the new and cooked ATF had already finished; the cooked Lucas then took over 7 minutes total to finish, narrowly ahead of the new Lucas which finished last of the four samples tested (new ATF, cooked ATF, cooked Lucas, new Lucas) | viscosity measured at almost 180, versus roughly 60 for 5W-30 motor oil, described as a very high viscosity product; flash point 455 F; additive package described as minimal, mainly boron, calcium, and phosphorus, with the main apparent function being to increase the viscosity of the existing transmission fluid rather than add detergents/dispersants | for comparison, the vehicle's own transmission fluid tested within the normal viscosity range for ATF (lower than 5W-30 motor oil) with a flash point of 410 F | tested on a 2000 Honda Accord (3.0L VTEC, 4-speed automatic, over 220,000 miles) that a transmission shop had diagnosed as needing a full rebuild due to a bad torque converter, with a known slip/hesitation and a failure to shift smoothly from second to third gear; after adding a full 24 oz bottle and driving 5 to 10 minutes, the second-to-third shift showed quite a bit of improvement and shifted a little better than before, but the underlying problem was not fixed |
How it was tested
- evaporative loss test (weight loss after 2 hours at approximately 300 F)
- lubricity / film strength test
- cold flow test at -20 F (new and heat-cooked samples)
- independent oil lab analysis (viscosity, flash point, additive package)
- real-world road test on a worn transmission before and after treatment
“Unfortunately, it did not fix it. However, it did seem to make quite a bit of improvement regarding the second-third shift, and it just seems to shift into gear a little bit better than before.”