A truck earns money when it is moving. SFR goes in the systems that take it off the road — engine, differentials, manual gearboxes — and in the fuel, where dirty injectors quietly cost you miles per gallon.
Every fortifier follows the same published dose — 1½ oz per quart (5%) the first time, 1 oz per quart (3%) at each change after — except where friction is part of how the unit works. Those rows are marked.
| System | Product | Dose | Why |
|---|---|---|---|
| Diesel engines | D-SOL Diesel Engine Oil Fortifier | 1½ oz per quart (5%) first application · 1 oz per quart (3%) at each change after | Built for diesel: extra detergent for soot, extreme-pressure protection for the valve train and bearings. |
| Gasoline and propane engines (pickups, service trucks) | GASZOL Gas Engine Oil Fortifier | 1½ oz per quart (5%) first application · 1 oz per quart (3%) at each change after | Add it to a latest-spec motor oil and you have a premium oil: extra detergents and dispersants, corrosion inhibitors and SFR's extreme-pressure package. No sulfur or phosphorus, so it is safe with catalytic converters. |
| Differentials, manual transmissions, transfer cases (gear oil) | GEARZOL Gear Oil Fortifier | 1½ oz per quart (5%) first application · 1 oz per quart (3%) at each change after | Extreme-pressure fortifiers beyond most gear oils; corrosion protection when water gets in. Only where the unit runs gear oil — see the note below the table. |
| Limited-slip differentials | GEARZOL Gear Oil Fortifier | 1% only — these work on friction; more can cause slip | Posi-traction units work on friction — 1% and no more. |
| Automatic transmissions | Not recommended | Not recommended — friction is what makes it work | Automatics need friction to shift. Leave them alone. |
| Diesel fuel — summer | D-SOL Lubricity / Cetane | 1 gallon treats 400 gallons of diesel — every fill | Puts lubricity back into ultra-low-sulfur diesel to protect injection pumps and injectors; cetane boost. |
| Diesel fuel — winter and all season | D-SOL Multi-Function All Season | 1 gallon treats 400 gallons of diesel — every fill | Same lubricity and detergency plus cold-flow protection for winter fuel. |
| Mixed fleet, one product on the shelf | SFR-100 All Purpose Oil Fortifier | 1½ oz per quart (5%) first application · 1 oz per quart (3%) at each change after | The all-purpose fortifier for engines, gearboxes and petroleum hydraulics (not water-glycol) when you want one jug that covers the yard. |
Check what your manufacturer specifies for each unit. Many late-model transfer cases, and some manual transmissions and transaxles, call for automatic transmission fluid rather than gear oil. Rule of thumb: anything that calls for ATF (transmissions, transfer cases, trim and tilt units, power steering) gets no SFR fortifier, H-ZOL included. The one product for ATF is ProTecta Synthetic Transmission Treatment. A tractor whose hydraulics share one fluid with the transmission, wet brakes or PTO clutch gets 1% only. When in doubt, call 800-735-6438 before pouring.
Prices and treats-up-to are the shop's own figures. Quarts and gallons ship free over $100; pails ship boxed by FedEx Ground at a flat rate. Not sure how much you need? Use the calculator.
One gallon treats 400 gallons of diesel. At the gallon price that is 11.9¢ per gallon of fuel.
Numbers are the laboratory's, run at the leading independent labs in the U.S. — see Proof & Testing.
By the gallon jug, 9.0¢ per gallon of diesel with D-SOL Lubricity / Cetane and 11.9¢ with D-SOL Multi-Function All Season; by the pail, 7.5¢ and 10.2¢. One gallon of conditioner treats 400 gallons of fuel, every fill.
1½ oz per quart of oil on the first application, then 1 oz per quart at each oil change after. A 40-quart diesel sump takes 60 oz the first time and 40 oz at every change after, so a gallon covers three changes once you are on the 1 oz rate.
No. Automatic transmissions need friction to shift and SFR fortifiers reduce friction. Limited-slip differentials and hydrostatic drives are the friction exceptions: treat those at 1% and no more.
No. Add it to the oil that is in the engine now; it mixes with any petroleum or synthetic oil. Start the next change at the 1 oz per quart rate.
Yes — pull an oil sample before you treat and another at the next drain, and compare the wear metals. SFR's oil analysis program uses an independent laboratory and your own engine. See Oil Analysis on the home page.
Made by SFR Corporation under our ProTecta consumer brand. Buy them at protectaoil.com or from your SFR distributor.
Pull an oil sample before you treat and another at the next drain, and compare the wear metals. Same independent lab, your machine, your numbers. Or call 800-735-6438 with your equipment list and we will spec and price it.
