Keeping Ram Tough

If you are thinking of buying an older model Dodge Ram to add to your fleet, these tips will help make that used purchase a solid one


By G.R. Whale



The HD Dodge Ram pickups make excellent workhorses. They are stout with a loyal owner group who seldom part with them. It’s not unusual to see owners keeping them 20 years and putting on more than 300,000 miles before the keys are handed off to someone else – or the truck parted out.

Still, used ones with far less miles and years on the frame are not hard to find. But like all vehicles, different years and models had little mechanical hiccups along the way.

Throttle-position sensors (TPS, aka APPS) fail on 5.9s from 1998-2004.5, and some replacements weren’t adjusted properly. A sensor-only replacement, as opposed to the earlier assembly is about 60 percent cheaper.

A good portion of those problems can be attributed to modified engines (the Cummins is a favorite among the diesel hot-rodding crowd); overloading (hot-shot drivers and RVers don’t seem to care about GCWR); or from being improperly serviced (not following proper maintenance schedules or fluid specs).

We spoke to Dodge/Ram technicians in and out of dealerships, ASE Master Techs Mike Mullenax and Andy Redmond in Texas, and Robert Patton, publisher of the Turbo Diesel Register Ram/Cummins club magazine for their input when it comes to shopping around for a used HD Ram.

Here are a few things they say to look for as you narrow the search for your next Dodge/Ram HD.


Gas Engines

The 5.9 Magnum V8 and V10 engines were well sorted by 2000 and prove quite reliable. Truck 5.7 Hemis were susceptible to leaks around the thermostat housing and timing cover, intake valve springs went bad on some ‘06-08.

Scheduled maintenance is critical to the 6.7s operation. Replacement injectors should be matched to the ECM and the EGR should be cleaned every 67,500 miles.

Some Hemis would drop a valve seat if overheated, usually from aftermarket supercharging or overloading, and a dirty injector leaking into a cylinder would often hydro-lock it at startup.

Andy Redmond of Redmond Enterprise and Engine in Texas says he sees sludge build-up on 5.7s run on 5W20 and recommends full synthetic for all Hemis working in in hot environments.


5.9ISB Diesel

Later versions of the ISB – after the loose dowel pin and 53 block issues – with the VE44 injection pump proved reliable, with ancillaries usually the weak point.

Primary among these is lack of volume or pressure from the fuel transfer pump that kills the pricy VE44 pump. Aftermarket pump/filter arrangements from FASS, Airdog, Glacier Diesel, Geno’s, Vulcan Performance, etc. often have more robust pumps and better filtering, both beneficial.

A fuel pressure gauge, or LED low-warning light kit, should also be installed and monitored to protect the VE44. Redmond notes the warning-light kit sensors don’t usually last a year without an isolator in the loop.

Throttle-position sensors (TPS, aka APPS) fail on 5.9s from 1998-2004.5, and some replacements weren’t adjusted properly. A sensor-only replacement, as opposed to the earlier assembly is about 60 percent cheaper.

Note, over-oiled aftermarket air filters often trigger dirty MAP or IAT codes, and cam or crank position problems are generally wiring corrosion or chafing against AC or other engine components – the sensors themselves are very reliable.

ECMs built in the ’99-01 time frame are starting to fail internally, but there’s no set of part numbers to tell if yours will.

Certain vocations may find the oil filler breather relocation kit useful (it loses lots of oil on steep descents) or the cold-idle reflash that raises idle speed and drops three cylinders to build heat in sub-freezing ambient, < 140 degrees F coolant, temperatures.


5.9ISB HPCR Diesel

In 2003 the Cummins added common-rail (CR) fuel injection, a system with plenty of benefits but one that demands clean fuel.

One big nuisance item in the steering system is the weak
track bar. BD Diesel and others have heavy-duty replacements to cure those ills.

Early engines with CR had the same TPS/APPS as ’98-02 and lift pump issues, especially those mounted to the filter housing, and the 2003 trucks suffered from corrosion at the PCM.

A fuel transfer pump failure won’t damage expensive parts in CR engines but it might not start either. In 2005 the pump was moved into the tank, and Dodge no longer sells 03-04.5 units, they use a retrofit kit to 2005 style.

As Patton notes, moving a potential wear item to a harder-to-service location is counterintuitive, and the aftermarket offers better replacements. Many of these stock-style pumps will support up to about 100hp increases.

Though it has many sensors, say our experts, following proper starting procedures often cures phantom “problems.”

Surging complaints typically indicate a bad fuel-control actuator; they’ve been known to fail.

Less common, and occasionally overlooked, is a bad cascade overflow valve on the CP3 producing hard or no starts. Some techs recommend a lubricity additive for corrosion resistance.

Older, high-mileage 4×4 Rams benefit greatly from upgrading to Dynatrac’s manual-locking hub conversions that include easily serviced bearings for ’94-09 trucks.

Redmond also finds some ’04 diesels drop a valve seat insert (usually cylinder #4 or 5). Be sure to check service records to see if the truck you are buying has had these types of repairs.

CR injectors fire multiple times per cycle, at pressures beyond 20,000 psi, so they wear faster than old ones. The #4 injector isolator/hold-down bracket often wears a pin-hole leak in the line, yielding poor performance and a messy engine bay.

TSB 14-004-11 details a Mopar fuel filtration kit, including fuel tank vents hoses, that costs about the same as one injector.


6.7 ISB

Introduced to Dodge trucks in 2006, the 6.7-liter ISB, derived from the 5.9L, met 2010 emissions requirements and had an exhaust brake built-in.

Many of the early “problems” revolved around lugging the engine: sooted turbos, EGRs and DPFs, and plugged NOx cats. All issues attributable to not working the engine hard enough.

The variable geometry turbo has an electric motor to move vanes for better throttle response, boost and 150 braking horsepower. But excess soot could limit vane movement, impairing all those performance factors. So be aware of the soot issue when shopping for that used model.

Software re-flashes solved sooting issues so be sure they’re up to date. (In Redmond’s experience, emissions equipment problems were far fewer than Ford and GM diesels.)

Ball-joint upgrades, like these from ProSteer, are highly recommended when the OE parts bite the dust.

He does note, however, that “early 6.7s have a fairly rough cylinder head deck finish which sometimes leads to mysterious coolant loss, with combustion pressure seeping into the cooling jacket and misting out from the coolant recovery reservoir.”

Scheduled maintenance is critical to the 6.7s operation. Replacement injectors should be matched to the ECM, the EGR should be cleaned every 67,500 miles and fuel filter changes done every 15,000 miles or less are required.

Our experts also suggest cleaning the DPF at 100,000 miles by washing and/or blowing compressed air backwards through it.



Automatic transmissions operated at OEM power and weight limits rarely fail. But pushing past those limits causes big issues. That’s why there’s a big aftermarket for strengthening them to hold up to the power generated by a tune.

Leaks in trans fluid cooler lines are not uncommon, especially since they usually hide behind something and observers may fail to take into account engine movement when examining them.

Contaminants get in where rubber meets metal hose and etch a fine hole, misting the undercarriage with no obvious leak point.

Dodge reminds owners that ATF+4 color and odor are not indications of fluid condition and should be changed on mileage/use.

By this point the NV4500HD five-speed manual was solid, although many hi-milers find the called-for GL4 is better for them than supposedly backward-compatible GL5.

Although interior noise, vibration and harmonics increase, Redmond prefers a single-mass flywheel be used to cure any clutch-slip issues instead of using the dual-mass model used on G56R trucks.

However, before you go flywheel hunting, our techs say most Ram clutch-slipping complaints are usually traced back to faulty master or slave cylinder leaks.



By 2002 the brakes were all-disc and the central-axle disconnect was dropped so the front driveshaft is always turning. So always check the front diff fluid level even if you never engage 4WD on ’02-newer 4WD Rams.

4WD front hubs are not easily serviced and Redmond finds the ’03-‘09 bearings and ball-joints inferior to those used in earlier models. But he does consider the “H46” recall adequate.

If you will be using 4WD a lot, our experts recommend upgrading to Dynatrac’s manual-locking hub conversions that include easily serviced bearings for ’94-09 trucks (‘10+ in testing). Dynatrac (rebuildable) and Carli also carry ball-joint upgrades.

Track bars are the biggest nuisance to Ram owners, up to the 2010 model year. The ’00-‘02 bar wears quickly because of the weak ball stud end.

There are many fixes including Luke’s Link, DT, BD, Moog DS1413. But Redmond prefers the Solid Steel Industries relocation bracket with the ’03-‘08 factory or Solid Steel’s own adjustable track bar.

Tie-rod ends on ’08-newer models were an issue, and Dodge issued a TSB with instructions for indexing the ball stud. Our sources suggested this was more a metallurgy issue than indexing. So check them out if this is the truck you are thinking of buying.

Other steering upgrades include those from Rock Solid for Gen 2 trucks, Borgeson shafts and boxes, steering box stabilizers from BD and others, and a Saginaw 1400 series-box upgrade from Performance Steering Components.

Maintenance tips: keep at least 0.5-degree U-joint angles to keep them lubed; fill the 2004 axle ¾-inch below fill hole to keep it from foaming; jacking up one side at a time ensures the wheel bearings get lubed and level is set properly.

(On trucks built after 2004 there should be a stamped fill line about ¾-inch below the fill hole.)


Bodywork and Electrics

The TIPM (Totally Integrated Power Module) in ‘03-09 trucks has more issues than other components, often traced to trailer lights and insufficient fusing; after cycling like a circuit-breaker a few times the TIPM becomes an expensive paperweight.

A separately wired fuse/relay circuit for trailer running lights removes that load.

Top-line audio and navigation systems are usually fixed with software via flash or DVD, but the aftermarket or your smartphone are often more cost-effective.

If your Ram’s remote start cranks but doesn’t start the truck (Redmond: “WCM wigged out”) try pulling the IOD fuse for a couple of minutes to reset the system.

Vent heater blend doors on early Gen 3 trucks were problematic with the metal rods holding the doors breaking off so the A/C and defrost wouldn’t work right. Dodge thinks these parts are solid gold by their price. Fortunately, Heater Treater ( has better replacement door kits at a good price with detailed instructions to fix such A/C heat/vent problems.

Paint on Gen 2 and 3 is another big problem – especially red. It’s the most costly of colors for repainting, too. Repainting with today’s more UV-resistant paints is the only solution if you want to keep rust at bay.

With all the floods and hurricanes over the past 7 years, be diligent checking for water damage when inspecting a used pickup.

Look for rust under the seats, up under the side corners of the dash, down in the cowl or on top of the frame – or anywhere trash and debris might have lodged and whomever cleaned it up missed.





Rams are usually classed by generation such as Gen 2 (’98-’02), Gen 3 (‘03-’09) and Gen 4 (2010-present). Diesel engines are classed by fuel system, and model years ending in .5 indicate those built after January 1 of that year.

Gen 2 Ram HDs offered 245hp 5.9L V-8 and 300hp 8L V-10 gas engines, Cummins 5.9 ISB diesel (235-245hp/460-505 lb-ft), 4-speed automatic, and both 5- and six-speed (diesel) manual transmissions. GCWR maxed out at 20,000 pounds.

Gen 3 saw a lot of changes during its six years including the entry of the common-rail ISB diesel (235-305 hp/460-555 lb-ft) and 345hp 5.7 Hemi and five-speed automatic. 2002 was also the last year for V10.

Extended service intervals came into play as did rack-and-pinion steering on 2WDs, and a helical-gear limited-slip that required no additives. Max GCWR increased to 23,000. By the end of 2004 the 50-state diesel rating was 325/610.

For 2005 the G56 6M phases out the NV5600; 2006 adds the MegaCab body, and in Spring the 2007 Chassis Cab arrives: Hemi or 6.7L ISB VGT (variable geometry turbo) with integrated exhaust braking, rated 305/610. Ram pickup keeps the G56 and 48RE transmissions while the Chassis Cab gets G56 or Aisin AS68RC wide-ratio six-speed auto.

After 1/1/07-build pickup uses 6.7L diesel ($500 more than 5.9L but includes exhaust brake and required emissions system is separate option at $995) at 350/650 with new 68RE six-speed automatic; 350/610 with revised, taller-ratio G56R.

2009 sees the Hemi jump to 383 hp depending on duty cycle while the 6.7L got revisions to turbo, EGR cooler and fuel filtration.




Any owner or tender of a Dodge Ram should know about and how to use Chrysler’s service website,, and the enthusiast websites and publications,,,  and the Association of Diesel Specialists. Be familiar with Cummins and Bosch shops often less expensive than dealer fixes, and know the CPL (control parts list) number(s) for your Cummins.









Borgeson Steering,, 860-482-8283

DT Pro Fab,,




FASS,, 866-769-3747

Geno’s Garage,, 800-755-1715

Heater Treater,

Performance Steering Components,, 812-270-0102

Redmond Enterprises & Engine, Plano, Texas,


Rock Solid,, 936-250-1323

Solid Steel Industrial Mfg.,, 306-842-4346

Turbo Diesel Register,, 770-886-8877

Vulcan,, 800-991-7996