Description
68157291AA Fuel Filter — Ram 6.7L Cummins (2010–2020)
The 6.7L Cummins in your Ram HD truck is a million-mile engine — but only with clean fuel. The 68157291AA fuel filter is the rear (chassis-mounted) filter in Ram's two-stage filtration system, rated at 5 microns to protect the Bosch CP3/CP4 high-pressure pump and piezo injectors from wear. At a fraction of the dealer price, this filter gives you OEM-grade protection without the dealership markup.
Vehicle Fitment
| Year |
Make |
Model |
Engine |
| 2010–2020 |
Ram |
2500 |
6.7L L6 Cummins Turbo Diesel |
| 2010–2020 |
Ram |
3500 |
6.7L L6 Cummins Turbo Diesel |
| 2010–2020 |
Ram |
4500 |
6.7L L6 Cummins Turbo Diesel |
| 2010–2020 |
Ram |
5500 |
6.7L L6 Cummins Turbo Diesel |
Also fits 2010–2012 Ram 3500 Chassis Cab (different from 3500 pickup — verify filter location).
Two-Stage Filtration: Why This Filter Matters
Ram engineered the 6.7L Cummins with a two-stage fuel filtration system: the front filter (underhood, 68065612AA cap) handles primary water separation, while this rear filter (frame-mounted, 68157291AA) provides final 5-micron polishing before fuel reaches the high-pressure pump. Skipping filter changes — or using a budget 10-micron "will fit" filter — is the #1 cause of premature CP4 pump failure in these trucks. At $8,000–$12,000 for a CP4 replacement, a $20 filter is the best insurance you'll ever buy.
Key Specifications
-
Filtration Rating: 5 micron absolute — catches particles the size of a red blood cell
-
Dual-Layer Media: Outer layer separates water; inner layer filters fine particles
-
Plastic End Caps — prevent filter element deformation under pressure
-
Replace OEM: 68157291AA, 68065608AA, MO608, MO291, PF9870, L6806F, FS43255
-
Designed for the Ram two-stage system — rear (chassis) filter position
Cross-Reference: Every Compatible Part Number
| Part Number |
Brand |
| 68157291AA |
Mopar (current OEM) |
| 68065608AA |
Mopar (previous PN, superseded) |
| MO608 / MO291 |
Mopar (service kit numbers) |
| PF9870 |
ACDelco / GM |
| L6806F |
Luber-Finer |
| FS43255 / FS53000 |
Fleetguard (Cummins Filtration) |
| CS11037 |
Hastings |
| FF1199 |
Baldwin |
| 4947561 |
Cummins |
| 33255 |
WIX |
Filter Replacement Interval
-
Standard duty: Every 15,000 miles or 12 months
-
Severe duty (towing, dusty conditions, biodiesel): Every 7,500 miles
-
Water-in-fuel light on: Drain water separator AND replace filter immediately
- Always replace both filters (front + rear) at the same time — a new rear filter behind a clogged front filter is pointless
Replacement Procedure Overview
- Locate the rear filter housing on the driver-side frame rail, just ahead of the fuel tank
- Place a drain pan underneath — expect 1–2 quarts of diesel spillage
- Open the water drain valve (yellow lever) and drain into the pan
- Unscrew the filter cap using a socket or the iFJF 61150 wrench
- Remove old filter element, replace O-ring on the cap
- Insert new filter, ensuring it seats fully in the housing
- Tighten cap to 18 ft-lbs — do not overtighten
- Cycle key to RUN (without starting) 3–5 times to prime the system
- Start engine, check for leaks, clear any DTC codes
FAQs
Is this the front or rear filter?
This is the rear (chassis-mounted) filter — the one under the truck on the driver-side frame rail near the fuel tank. The front filter (under the hood) uses part number 68065612AA and a different element.
Will this fit my 2022 Ram 2500?
This filter fits 2010–2020 Ram HD trucks. For 2021+ models, verify your part number — Ram switched filter designs on some late-production trucks. Check your existing filter's number before ordering.
What's the difference between 5-micron and 10-micron filters?
A 5-micron filter catches particles half the size of a 10-micron filter. The CP3/CP4 high-pressure fuel pump in your Cummins has clearances measured in microns. Running a 10-micron filter may save $5 today but risks a $10,000 fuel system repair. Stick with 5-micron.
Do I need to replace both filters at the same time?
Yes. The front filter (water separator) and rear filter (final filtration) work as a system. If the front filter is clogged, unfiltered fuel bypasses it and overwhelms the rear filter. Always replace both as a set. iFJF sells the complete two-filter kit: SKU FJ-67AA-91AA.
🛠️ Complete Your Ram 6.7L Fuel System Service
Need more than just this part? These products are designed to work together:
