Product Reviews

CTM Dana 44 U-Joints

Article and photos courtesy of Eric Hummel, AKA Grim-Reaper

Well I have had old "Dollar" (my 75 Jimmy) for 4 years now. It went from a rusted out bone stock truck on 31's to it's current state of 35 inch BFG KM's, Lockers on both ends 7 ft tall trail beast. Once you get the lockers and 35's your pretty well in the zone where breaking parts is not a question of "if" as much as a question of "when". The most common failure is front axle U-Joints and axle shafts. There are only a couple of options at this point to fix this problem. My plan for my truck is that the truck will stay on 35's. I do some occasional trailer pulling and I do enjoy driving my truck to work on nice day's so this is a good blend of Trail and street.

The first solution to my problem would be to replace the axles with axles from a 1 ton doaner truck. This would get me a massive and strong Dana 60 front axle and a even stronger 14 bolt full floater for the rear end. You can't argue that this is the ultimate in strength that is as close to bolt on as it gets. Problem is cost. Those $500 D60's are few and far between. The D60 front is around $1200 for a rebuildable unit that you could easily sink $500 into parts to rebuilding and replacing seals. The 14 bolt rears are reasonable but you might still have some money to sink into that to get them up to snuff. The drum brakes are so massive the most of the time a Disc brake conversion is performed. The 1 ton gear is 8 lug so you are also looking at a set of rims to buy.

As you can see, your quickly over $2,000 if you stay with your current tires if you get lucky and the axles you buy is in good condition. You also loose a fair amount of ground clearance and to get back to the clearance I have with 35's, I would have to step up to 38's. That means about $800 or better for tires and more modifications to the truck. You could be pushing an easy $3,000 before your all said and done and loose some of the street friendliness unless I want to swap tires every time I go trail riding.

I follow some of the hard core rock crawling events. The current trend is purpose built tube buggies. Many of these trucks are running half ton running gear but when your only moving a truck in the 3,400 LB range your taking a lot of the stress off the axles. Part of the weight loss is saving about 500lb by going with ½ ton gear over 1 ton gear then upgrading the axle shafts and u-joints with alloy parts. Numerous companies offer upgrade parts such as alloy axle shafts and new super strong U-Joints are now on the market. The combination of the joints and the alloy axle shafts moves the failures to near what a stock Dana 60 axle shafts and u-joint will take.

Leading the pack of these new "super strong U-Joints" is CTM Racing. These u-joints, combined with a set of Warn alloy axles shafts, is a very popular combination that proves to be very reliable.. It's not cheap to upgrade to these parts but it is a lot cheaper than replacing the axles. To get the full set up you are in the $900 range. The parts are all lifetime warranty so if all goes well you are either not going to break these parts or you are going to have replacements for little more than the shipping costs to send them back to the manufacture.

I put in a call to CTM Racing and spoke with Jack Graef about the product. Jack is a wheeler so he understands what people into Offroading are looking for. He was at that same point most of us have been in with broken parts making a pile in the corner of the garage. He happened to be an expert machinist and decided to do something about it and make the strongest u-joints he could.

The results of his labors have revolutionized the sport. There are many wheelers that are using these joints in competition with outstanding results. I'm not going to lead you on here. Some have managed to break these joints but most of those people had been running them for a full season of competition. These are the same people that were changing out broken joints and axle shafts multiple times in a weekend. Now they are going several competitions before failures. This is not the type abuse the average guy is going to subject their truck too. For most of us these joints, with proper maintenance, will out last the truck we install them in.

The original CTM joints were carved out of a single puck of 300m chrome molly Even with the CNC machines that Jack uses this was a very intensive operation to create these. The amount of machining that was needed was going through tooling at a pretty quick rate. CTM went to a forged piece to get the basic shape and reduced the amount of machining needed to make the joint. Same materials but less work to create so more cost effective for CTM to produce. So don't be surprised when yours look a little different than most of the pictures that are floating around. These are still just as strong and faster to produce. That means your not going to have to wait as long to get yours.

My CTM joint arrived at my house just in time for Dixie run. I wasn't in the door more than 5 minutes before I had the box open. Another 5 minutes I was out in the shop getting grease on my work clothes (My wife just loves when I do that) digging around for a 297 joint to compare to the CTM. There is not a picture in the world that truly shows you how massive this joint is. Till you have one of these in your hand you will not understand what makes them so strong.

Pictures do not justice to the size difference

The first thing you will notice when you remove one of the caps is no roller bearings are used in these joints. A roller bearing has a very small surface area that is supporting the load. A major failure in a traditional u-joint is overloading the bearings and causing them to shatter. Once the bearings shatter it allows the cross to cock sideways and the bearings on the opposite end will shatter. Once this happens the joint will either spit the caps or twist the ear of the axle shaft sideways. This causes either the ear or the cross of the shaft to fail or the cross pulls out of one of the ears. If your lucky you heard the joint fail and you get out of the throttle before the yokes of the shaft act like a guillotine and cut the end of the lower ball joint off and cause the knuckle to come off the axle.

The bearing surface in the CTM is a bronze piece in the caps. The tolerance is extremely tight so the actual surface area carrying the load is much larger. The extra space that normally is used for the bearings is now free to use to make a larger pin diameter on the cross and a thicker wall in the caps. This makes the joint more ridged so that it can't flex as easily. Since it can't flex as easy that means it's not twisting the ears on the axle shaft. The load is evenly distributed on the thicker walled cap so you not likely to see the cap split in half. The caps are also retained with a full circle C-Clip. The 2/3c-clip tradition joints use are prone to being spit out.

Little details were not over looked on this joint. When the transition is made from the cross to the body the area has been radiused. If this area had been a straight 90degree cut it would have created a potential weak spot. The joint is not cross drilled. Removing material from the cross could cause a weaker product. These joints are greasable but the grease fitting is in the caps where they will not compromise the strength. Because the joint is a harder material than the bronze sleeve in the caps the cross should not see any wear. This makes the joint rebuildable should you wear out the bearing surface. If you keep up the maintenance this should be a long way down the trail.

Bottom line is Jack did his homework on this product. He studied the failures and came up with solutions to help prevent those problems. Every trick that he could come up with to make a stronger product was used.

I will stay true to form in most of my write-ups and include some of my overly details instructions that most of you have come to expect out of me.

The CTM does have an installation procedure that you must follow. If you don't follow the steps in the included instructions you might as well go start banging your head into the nearest wall. You're simply not going to be able to install the joint if you deviate from the instructions at all.

First step in the installation process is to make sure that the ears on the axle shafts are clean. It would be a shame to damage these joints because of a little dirt that was transferred off a dirty axle shaft. These joints must be installed in an axle shaft that will except the full circle c-clip. Basically I would not recommend messing with a stock shaft. This joint is much stronger than a stock shaft. The whole point is to avoid breaking parts right? Why put a very expensive u-joint into an inferior grade shaft? CTM recommends using a good quality alloy axle shaft. The shafts that Warn sells seem to be a very good match to these joints and what I am using.

Close up

Looking at the joint you will notice that each face has a beveled off area. This serves two purposes. The first is it allows you to tilt the joint into the ears on the axle shaft. The second is to allow the room needed to install the Full circle C-Clip.

The install procedure starts by removing the caps. Place C-Clips over both pins of the cross that you are starting with. Angle the joint into the ears on the axle shaft. Once the shaft is in the yoke then slide the O-Rings onto the cross.

Start by removing the caps	Place C-Clips over both pins

You must install the cap opposite the beveled side first. Use a joint press or a shop press, it is the only correct way to install these. A hammer and a socket as a good way to deform the caps and cause you problems on down the road. You can buy a joint press for a very reasonable price at places like Harbor freight and you will get a lot more use out of this tool then you would think. Press the cap in far enough that you can install the C-Clip and do so. You want to open the C-Clip just enough to make it over the cap. If you over extend this style clip you could weaken them. This should not be a problem if your using the correct tool.

Installing the second cap is no different than that the first. Press the cap in till you can install the C-Clip. At this point it will become obvious why that bevel in the face is important. This will allow you enough room for the tool to access the C-Clip for installation. Repeat the process for the other section of shaft.

Now you can install the shaft into the axle housing. Once back in the axle you can install the Zerk fittings and grease the joints. These style Zerk fittings use a special Needle style tip that I have pictured below.

Install the shaft into the axle housing	This is the proper tip for these style Zerks

You don't want to use the tip that is an actual needle. They will not work correctly. After you use this tip a few times you will find it's very handy and works on most Zerk fitting equally as well. It's narrow enough to get into the CV joint and u-joint where the standard tip will not fit. I hardly ever use my standard tip. Only problem with this tip is finding them.

Maintenance:
As with any bearing these joints do need regular maintenance. Dirt and water are big enemies of any u-joint. My typical maintenance routine is to relube the whole truck after EVERY trail ride as soon as I can. I wheel the Southeast and most of the trails I run involve mud or water. I make it a point that I check hubs, axles, transfer cases and anywhere else that water contamination could cause a problem within a day or two of the trail ride. I would recommend you get in the same habit. If this is a dedicated trail truck that only gets driven every couple of weeks and your normal maintenance is to lube before a trail ride but let it sit without maintenance after, well it's to late and parts are rusted and damaged. Lubing the joints as well as the ball joints and tie-rod ends within 24 hours of your ride will pretty well eliminate most water damage caused in these parts.

Summery:
Well what can I say. I have achieved a lot of piece of mind with the CTM's. I run sections of trails where I know people break joints and shafts all the time and I don't sweat it at all. I have hammered on my truck a lot harder with less worry. I had a reputation of "Mr. Pussy foot". That's probably why my parts breakage was low but it's also the reason I spent a lot of time on the end of a winch cable or a strap. Course I made up for that time by not having to fix my junk holding the rest of the group up but fear of breaking those weak front shafts always sat in the back of my mind. Now.....Hell My right foot gained about 200lb! I'm not nearly as likely to take the winch cable.

For those of you that are in the "Gray Zone" of when to go from ½ ton running gear or 1 ton running gear. This might be a good solution for you. Our trucks are heavy. Where a guy could get away with 297 joint and 35's on a 4,000lb Jeep and almost never break, most of us with K5's full of trail gear are pretty close to 6,000 lb with passengers. If your plan is to stay around 35-36 inches of max tire diameter then this is probably a very good choice for you to invest in.

Where to Buy:
Well you can get them right here On CK5's Sister site. http://offcamber4x4.com Or you can go to
www.CTMRacing.com You can order online or you can call directly at 949.487.0770.

I have to say I called and placed my order. I was lucky enough to have Jack answer the phone. Jack is one of those folks that is great to talk with. He stands behind his product and will take the time to answer your questions about any of his products. Maybe one day I can afford a set of those sweet portal axles he builds!