2020-2022 Ford 6.7L Powerstroke Charging & Starting Parts

Charging and starting on the 2020-2022 Ford 6.7L Powerstroke

Ford builds the diesel Super Duty with two batteries, not one. The owner's manual calls for a pair of Motorcraft BXT-65-750 units, which are Group 65 batteries rated at 750 cold cranking amps. The primary alternator on a 2020 F-250 or F-350 diesel is either a 175-amp unit (HC3Z-10346-C) or a 220-amp unit (HC3Z-10346-G). Trucks built with the dual-alternator option add a 157-amp secondary (HC3Z-10346-F) next to the primary. For cold starts, the 6.7L uses one ceramic glow plug per cylinder rather than an intake grid heater.

What fails and why

Most hard-start complaints on this engine come down to three things: weak batteries, voltage drop across the cables and grounds while cranking, or a failed glow plug. You'll see an extended crank, or a truck that won't light off on a cold morning. Battery age matters, and three to five years is the typical window. Because the two batteries age together, one bad battery drags the good one down with it, and you get slow cranking, dash resets and hard starts after the truck sits. That's why load-testing both batteries and checking voltage drop under crank comes before you blame glow plugs or fuel.

The charging side has its own pattern. A truck carrying a winch, a plow or upfitter equipment can ask for more current than a single alternator makes, and you'll see low-voltage warnings while it idles under that load. Ford's own answer is the factory dual-alternator setup.

Stock replacement vs. upgrade

If your truck is stock and its job is daily driving and towing, OE-replacement batteries and a 175- or 220-amp primary alternator keep Ford's charging strategy intact. If you've added electrical load, you have two routes. Ford's engineered path is the 157-amp secondary alternator with the dual-alternator bracket. The aftermarket route is a high-output replacement alternator, like the 300-amp Mean Green unit in this collection. Either way, fix the basics first. A bigger alternator does not fix voltage drop across the cables or a battery that fails a load test.

What we carry

Mean Green supplies the MG1627 300-amp high-output alternator and the 6696 gear reduction starter. XDP MFG adds its XD352 HD high-output alternator in wrinkle black and the XD423 HD replacement battery cable set for 2017-2022 trucks. Fleece Performance Engineering makes a charging circuit harness built for the 2020-2022 6.7L. On the battery side, this collection carries hold-downs rather than batteries: billet hold-downs from S&B and SPE Motorsport, and a hold-down kit from No Limit Fabrication. Lucas Oil Sure Start starting fluid rounds it out.

Fitment notes

Order alternator parts by whether your truck has one alternator or two. On 2020 trucks, single- and dual-alternator setups use different brackets and different mount bolts (M10x40 vs. M10x90). Don't cross-shop with the gas trucks either: the 7.3L and 6.2L gas alternators carry different part numbers and amperages from the 6.7L units. Read the year range in every title. Some parts here are listed for 2011-2022 or 2017-2022, and the Fleece harness is 2020-2022 only. Chassis cabs share this engine but are a separate product line from the pickups, so confirm fitment by VIN with the checker on the product page.

Frequently asked questions

My 6.7L cranks long on cold mornings. Is it the starter?

Usually not. Weak batteries, voltage drop on the cables and grounds during cranking, and failed glow plugs are the most common causes of hard cold starts on this engine. Load-test both batteries and check voltage drop under crank before you replace a starter.

Should I replace both batteries at the same time?

That's the safe call. The two batteries age together, and a failing one drags the good one down. Test both, and match the factory spec when you buy: a pair of Group 65, 750 CCA batteries, which is what the Motorcraft BXT-65-750 is.

How do I know if my truck has dual alternators?

Dual-alternator trucks carry a second, 157-amp unit alongside the primary. Owners report Ford bundled the option with high-draw equipment such as a winch or a rapid-heat system. It matters because the brackets and mount bolts differ between single- and dual-alternator trucks, so check before you order.

Is a 300-amp alternator worth it on a stock truck?

Only if you're drawing more current than the factory system makes. A stock truck with a healthy 175- or 220-amp primary keeps Ford's charging strategy intact. If you run a winch, plow or upfit and see low-voltage warnings at idle, a high-output unit like the Mean Green MG1627 or the XDP XD352 HD is one way to cover it. Ford's 157-amp secondary alternator is the other.

Do these parts fit a 2023 or newer Super Duty?

Only where the listing says so. 2023 brought the all-new fifth-generation Super Duty. The SPE Motorsport and No Limit Fabrication hold-downs are listed through 2024, while the alternators, starter, cable set and harness here are listed through 2022. Go by the year range on each product.

Not sure what fits? Call the shop at the number in the header, or use the fitment checker on any product page. We install everything we sell.