If you're stuck under the hood looking for a 2019 ram 1500 5.7 belt diagram because your serpentine belt just decided to call it quits, you've come to the right place. It's one of those things that seems simple until you're staring at a tangled mess of rubber and six or seven different pulleys, wondering which way is up. The 5.7L Hemi is a workhorse, but like any engine, that main belt is the lifeline that keeps your alternator charging, your AC blowing cold, and your power steering actually working.
Let's be real: trying to remember how a belt wraps around a half-dozen spinning wheels after the old one has already snapped or fallen off is a nightmare. Most of the time, there's a little sticker under the hood with the diagram, but those things fade, peel off, or get covered in road grime over the years. If you're reading this, yours is probably long gone or unreadable.
Getting the Layout Right
The 2019 Ram 1500 with the 5.7L Hemi has a pretty specific routing path. Before you even touch the new belt, you need to visualize the "snake" path it takes. On this specific year and engine, the belt starts at the crankshaft pulley (that's the big one at the very bottom). From there, it heads up toward the water pump and loops around the alternator at the top.
One thing that trips people up on the 2019 model is whether or not they have the eTorque system. If you've got the mild-hybrid eTorque setup, your belt routing is going to look a bit beefier because that motor-generator unit sits right where a traditional alternator usually lives, but it's much larger. For the standard 5.7L Hemi, though, the path is fairly straightforward once you see it laid out.
It generally goes: Crankshaft to the tensioner, over to the AC compressor, around the water pump, up to the alternator, and back down through an idler pulley. If you miss even one "groove" or go on the wrong side of an idler, you're either going to have a belt that's too loose to do anything or one so tight it'll snap as soon as you turn the key.
Tools You'll Actually Need
You don't need a massive rolling tool chest for this job, but having the right stuff makes it way less frustrating. You're definitely going to want a long-handled 3/8-inch or 1/2-inch drive breaker bar or a dedicated serpentine belt tool. A standard ratchet works, but the space in the front of the Ram's engine bay can get tight, and you need leverage to fight that tensioner spring.
The tensioner on the 5.7 Hemi is surprisingly strong. You'll be rotating it (usually clockwise) to take the pressure off the belt. If you're doing this solo, it's a bit of a balancing act—holding the tensioner open with one hand while trying to loop the belt over the final pulley with the other. If you have a buddy nearby, now is the time to trade them a drink for five minutes of help.
Step-by-Step Replacement
First off, make sure the engine is cool. Working around a hot Hemi is a great way to lose some skin. Once things are chilled out, locate the automatic belt tensioner. On the 2019 Ram 1500, it's tucked toward the passenger side, slightly lower than the alternator.
- Release the Tension: Put your breaker bar into the square hole on the tensioner arm. Pull it to release the grip on the belt.
- Slide it Off: While holding the tensioner back, slide the belt off the topmost pulley (usually the alternator). Once it's off one pulley, the whole thing will go slack, and you can let the tensioner go back to its resting position.
- Snake the New One In: This is where the 2019 ram 1500 5.7 belt diagram is your best friend. Start from the bottom. Wrap the belt around the crankshaft pulley first. It's the hardest one to reach, so get it out of the way.
- Follow the Path: Feed the belt around the AC compressor and the water pump. Make sure the ribbed side of the belt is touching the ribbed pulleys and the smooth side is touching the smooth idler pulleys. That's a common mistake—if you see the ribs touching a smooth pulley, stop and re-check your routing.
- The Final Stretch: The last pulley you want to go over is usually the tensioner or a smooth idler pulley because they don't have "lips" that catch the belt. Pull the tensioner back again, slide the belt over, and slowly release the tension.
Pro tip: Before you start the truck, do a quick "finger check." Run your hand along the pulleys (with the engine off, obviously) to make sure the belt is seated perfectly in the grooves. If it's off by even one notch, it'll shred itself within seconds of the engine firing up.
Why Do These Belts Fail?
The 2019 Ram isn't ancient, but three or four years of driving in heat, cold, and dust can take a toll. Serpentine belts are made of EPDM rubber these days, which is way better than the old stuff that used to crack and rot. Modern belts don't always show cracks; instead, they lose material in the grooves—kind of like how a tire loses tread.
If you're hearing a squealing sound when you start the truck in the morning, or if your steering feels heavy when you're pulling out of a parking spot, that's your belt (or the tensioner) crying for help. Sometimes, a pulley bearing starts to go bad, which puts extra heat into the belt and causes it to snap prematurely. While you have the belt off, give every pulley a quick spin with your hand. They should spin smoothly. If one feels "crunchy" or wobbles, that's your real problem.
A Note on the eTorque System
If your 2019 Ram has the eTorque system, things are slightly different. The eTorque motor uses a much thicker, more heavy-duty belt because it's actually responsible for restarting the engine during stop-start cycles. The tensioner for the eTorque system is also more complex.
If you're looking at your engine and see a massive unit where the alternator should be with high-voltage orange cables nearby, you have eTorque. The routing is similar in principle, but you'll notice the belt is wider and the tensioner might require a bit more muscle to move. The diagram for the eTorque version often shows a slightly different path to accommodate the larger drive unit.
Don't Forget the Tensioner
Most people just swap the belt and call it a day. But if your 2019 Ram has high mileage, the tensioner might be getting weak. A weak tensioner allows the belt to "slap" or vibrate, which wears out the belt and the bearings in your water pump and alternator.
A good rule of thumb is to replace the tensioner every other belt change, or if you notice the tensioner arm bouncing significantly while the engine is idling. It's a bit more money upfront, but it beats having to do the whole job again in six months because the belt slipped off.
Final Thoughts on the DIY Fix
Replacing a belt using a 2019 ram 1500 5.7 belt diagram is one of those DIY jobs that feels incredibly satisfying once it's done. It saves you a trip to the dealership and a couple hundred bucks in labor. Just take your time, make sure your routing is 100% correct, and don't force anything.
If you get stuck and can't find a physical diagram under your hood, just keep this path in mind: Ribs to ribs, smooth to smooth. As long as the belt is seated in the grooves and the tensioner has a good "bite" on the slack, your Hemi will be back to purring (or growling) in no time. Always keep an old belt behind the seat if it's still in "emergency" condition—you never know when you or a fellow Ram owner might need a backup on the side of the road.