Introduction:

For less than the price of a single tank of fuel, you can safeguard your truck from potentially thousands of dollars in damages! But why exactly does your truck need a driveshaft loop?

The Problem with Front Driveshafts:

The front driveshafts in heavy-duty Ram trucks are prone to failure due to a number of factors, and many are dependent on your generation of truck. The front driveshaft on any four-wheel-drive truck presents a unique challenge. Unlike the rear driveshaft, the front incorporates a Constant Velocity (CV) joint to accommodate the slight upward angles at both ends of the shaft. In the case of most of our trucks, the CV joint is, more specifically, a Double-Cardan style CV joint - more on that later. The output flange on the front side of the transfer case is at an upward angle, and so is the input flange on the front axle. A standard universal joint will bind under this geometry, so the solution is a Double-Cardan joint on the front driveshaft, at the transfer case. 

As seen in the illustration above, there is a ball and socket joint between the universal joints that keep each u-joint at the same angle, relative to the intermediate yoke. This is what makes this joint a “constant velocity” joint. This joint is CRITICAL to the life of the driveshaft. Proper maintenance, including regular greasing as recommended by Chrysler, is essential to prevent catastrophic failures. This ball and socket joint is responsible for most front driveshaft failures on our trucks. When the ball and socket joint fails, the pair of u-joints flop around, and run out of balance, and it will literally tear the transfer case apart! 

Greasing this joint is a challenge, and requires a special tip for your grease gun. It is not easy to find, nor is it in an easy spot to access. In my experience, it’s also difficult to tell whether or not the joint is actually taking grease. I’m not saying you shouldn’t grease this joint, but I am saying that I never get a warm fuzzy feeling after greasing mine. 

Below are images of the needle required for greasing the double-cardan ball, and the location of the grease fitting. 

 

Other Causes of Driveshaft Failure:

In addition to double-cardan failure, there are other factors that can cause a driveshaft failure. Sometimes balancing weights fly off of the driveshaft during operation, and cause vibration leading to a failure. Loose driveshaft bolts can cause the driveshaft to separate from the drive flange, causing damage to the surrounding components. Aggressive driving in 4-wheel drive can also cause a failure. Driveshaft loops are mandatory in most sanctioned sled pulling and drag racing rules!

The Domino Effect of Driveshaft Failures:

When a driveshaft fails, it can lead to a domino effect of damages. Often, the weakest link in the system gives way, which can be the transfer case. The free-swinging driveshaft, no longer restrained by the transfer case, can wreak havoc by damaging brake lines, transmission lines, fuel lines, wiring harnesses, transmission pan, and can even rupture the cab floor. The result? Costly repairs, including bell housings and transmission housings, and potentially dangerous situations such as fires caused by ruptured lines and sparks.

1989-1992 (1st Gen) trucks:

These trucks have manual locking hubs, and don't seem to have as many issues as the newer trucks. Unless the hubs are locked, the front driveshaft isn’t being driven while on the highway. There are, however, cases where manual locking hubs can fail "locked" and put your truck at risk for a driveshaft failure. Many folks convert their newer trucks to manually locking hubs to avoid front driveshaft failures!

1994-2002 (2nd Gen) Trucks:

The Center Axle Disconnect (CAD) system is supposed to prevent the driveshaft from spinning when you’re in two-wheel-drive, right? This is correct, however, the CAD systems seem to have had very poor longevity, and today, many of these systems are no-longer working. Many owners opt to delete these kits altogether so their truck goes in and out of four-wheel-drive reliably. A driveshaft failure can still occur on a truck with a CAD system. Many 2nd gen owners have asked for a driveshaft loop for their truck, and we currently have them in development!

2002 Ram 2500 and 3500 trucks do not have CAD, and fall into the same category as the 3rd gen trucks, below.

 

2003-2013 Ram 2500, 2003-2012 Ram 3500 (3rd and early 4th Gen) Trucks:

Unlike earlier models equipped with locking hubs or Center Axle Disconnect (CAD) systems, these newer trucks have front driveshafts constantly engaged with the front wheels. Although there isn't significant torque applied to these components, this continuous motion increases wear and tear. These trucks are NOTORIOUS for catastrophic front driveshaft failures.

 

2014-2018 Ram 2500, 2013-2018 Ram 3500 (Late 4th Gen) trucks:

These trucks have the same double-cardan joint as previous models, but Ram reintroduced the CAD system for these models. Driveshaft loops for these trucks have still been very popular among our customers. Many report that they spend a lot of time in 4-wheel drive, or that they drag race, sled pull or just enjoy the economical protection of a driveshaft loop.

 

2019-Up (5th Gen) Trucks:

The 5th generation Rams have a different joint at the transfer case. Instead of a double-cardan, Ram decided to use a more traditional style CV joint, like you might see on the half-shafts of an independent front suspension. We believe this change had to do with the problems owners were experiencing with their Double Cardan Joints. These joints, however, come with their own set of challenges. On trucks that have been lifted, even slightly, owners are reporting ripped grease boots on these joints. When the boots rip, the grease flies out, leaving the joint to dry out, and become contaminated with dirt and road debris. When these joints dry out, they too will fail with a high potential of damaging other expensive components.   

 

Ram 4500/5500 trucks:

2007-2018 Ram 4500/5500 trucks have a live front axle, like the 3rd gen pickups, and are just as, or more notorious for failures. These trucks are bigger, heavier, and harder to stop during a failure, especially if the driveshaft takes out a brake line.

One of our Ram 4500/5500 customers told us of a failure they experienced where the driveshaft took out a brake line during a failure at highway speed, putting the brakes out of commission. Smoke and flames, caused by sparks and leaking fluids, entered the cab through a hole the driveshaft put in the floor while he attempted to stop the truck. Luckily, he was able to get the truck stopped safely in this case. We developed our Ram 4500/5500 driveshaft loop kit per this customer's request. 

2019-Current Ram 4500/5500 trucks use CAD and a traditional style CV joint like the 5th generation pickups. Many customers still purchase driveshaft loops for these trucks for the affordable peace of mind. 

 

The Solution: Driveshaft Loops

Our driveshaft loops are specifically designed to prevent secondary damage during a driveshaft failure. While they don't substitute regular maintenance and inspection of your driveshaft, they serve as a proactive measure to minimize collateral damage in the event of a failure. By containing the driveshaft, they reduce the likelihood of harming other vital and expensive components.

Our driveshaft loop kits feature CNC laser cut, powder coated 1/4" plate steel construction, made right here in the USA. All necessary high-tensile hardware is included, there is no drilling required, and shipping is free! 

 

Conclusion:

In conclusion, investing in a driveshaft loop is a small price to pay compared to the potential damages and dangers associated with driveshaft failures. Don't leave the safety of your truck and your wallet to chance. Take proactive steps to protect your investment!

 

Links:

Driveshaft Loop Kits – Five Nine Fabrication