48RE Governor Pressure Solenoid 1994, new and ready to install. Fits the 48RE. Ships fast from the USA.
A Ram that launches in second or third gear, refuses to upshift until high road speed, or drops into limp mode with a governor code is the classic sign of a sticking governor pressure solenoid. This listing is a new Mopar-brand governor pressure solenoid cataloged under the 1994 year and the A518 reference, the same electronic governor design carried into the 46RE, 47RE and 48RE four-speeds. The 48RE itself was built for 2003-2007 Ram 2500 and 3500 trucks with the 5.9L Cummins, so the 1994 label is a catalog year for the RE family rather than a 1994 48RE truck. Read the fitment notes below before you order.
The older RH transmissions used a spinning hydraulic governor on the output shaft to tell the valve body how fast the truck was moving. The RE family replaced that with a computer-controlled solenoid. The PCM pulses this solenoid to build governor pressure in step with road speed, and a governor pressure sensor (transducer) mounted beside it reports back what pressure was actually produced. That governor oil pushes on the 1-2 and 2-3 shift valve bore plugs, so it directly decides when the truck upshifts.
On a 48RE behind a Cummins this matters more than on a gas truck, because the transmission runs higher line pressure and more torque. When the solenoid sticks or its screen packs up with debris, commanded and measured pressure stop matching, the PCM sets a code and puts the unit in limp mode.
Not every one of those is the solenoid. Worn valve body bores at the 1-2 and 2-3 governor plugs leak governor oil and produce the same early-shift, shuttle and late-shift complaints, and a failing transducer can feed the PCM a bad reading even with a good solenoid. Overdrive and direct clutch wear, the most common 48RE hard failure, can also look like a shift problem at first.
Pull the codes first and note whether they point at the solenoid or the sensor. Check the fluid level and condition with the engine running and the fluid hot. If the fluid is dark and the pan holds clutch material, the governor is not your main problem. With a scan tool, compare desired versus actual governor pressure while driving; a solenoid that is sticking will show actual pressure lagging or overshooting. Our 48RE shift solenoid symptoms guide walks through electrical checks on the solenoid circuits, and the Ram 2500 Cummins shift problems guide covers the rest of the shift diagnosis.
The listing carries the year 1994 and the A518 reference, and the part is the electronic governor pressure solenoid used across the RE four-speeds. Electronic governor control on these units dates from the mid-1990s; earlier RH units used the mechanical governor and take no solenoid at all. Because the solenoid changed over the years (O-ring style, connector and filter screen differ between early and late designs), compare the old part side by side with the photo before installing, or send us your year, transmission and VIN and we will confirm. Other years of this solenoid, plus every other part we stock for this transmission, are on the 48RE parts page.
If the valve body bores are worn, a new solenoid alone will not fix the shift timing. In that case the 48RE pressure control solenoid for the same year and a full 48RE overhaul kit are worth pricing alongside this part.
| Fits | 48RE 1994 |
| Part type | Governor Pressure Solenoid |
| Condition | New |
| Brand | Mopar |
| Reference | A518 |
| Ships | From the USA |
| Warranty | 1-year |
No. The 48RE went into 2003-2007 Ram heavy-duty trucks with the 5.9L Cummins. The 1994 on this listing is the catalog year for the RE-family governor solenoid design. Compare your old solenoid to the photo, or send your year and VIN before ordering.
It is a good idea on a high-mileage truck. The solenoid and sensor sit together in the governor body, both can set governor codes, and the pan is already off.
A sticking or contaminated governor pressure solenoid is a common cause of wrong gear starts on the RE four-speeds. Low fluid, a bad transducer reading and worn governor plug bores in the valve body can do it too, so check codes and fluid first.
Mopar ATF+4 or a fluid licensed to the ATF+4 specification. Check the level with the engine idling, fluid hot and the selector in Neutral.
Clear the codes with a scan tool and drive the truck through normal shifts for a few drive cycles so the PCM adapts. No special tool is needed for the solenoid itself.
