The 62TE has been around since 2007. In this edition of Fun With Transmissions, we are going to check out the 62TE compounder unit. We’ll look at how it works and some of the things we need to pay attention to when we are rebuilding the unit.
The concept was to take the 41TE (4 speed) and split the transfer/pinion drive with an underdrive/direct clutch to drive a double ratio to the final drive. Some of you old school guys might remember units like the Ford A4LD unit or the GM 4L30. The difference is that the A4LD and 4L30 used an overdrive gearset at the input for the transmission, whereas the 62TE has one for the output. Other than that, it’s the same concept.
Although this is classified as a six-speed fwd transaxle, there are 7 forward speeds due to the addition of a 4th gear prime ratio that is used during a 6-4 kick down (figure 1). This prevents a double swap of components allowing for a smooth kick down. With that, let’s take a closer look at how to go through the compounder unit.
The first thing to check out is getting the unit out of the case after the transfer gears are removed. After the retaining snap ring is out of the way, we need to pull the unit out of the main case. What might appear easy at first is not at all that simple because the compounder unit can be really stuck in there!
Typically getting the compounder out of the case involves a slide hammer and a special tool. Chrysler has a tool just for this operation (figure 2). There are aftermarket tools available, or with a little creativity, you can make your own.
Now that the compounder is out of the case, we can begin to disassemble it. Of course, the first thing we run into is the strange-looking snap ring down in the sun gear (figure 3). This snap ring holds the sun gear to the shaft, and the tabs on the snap ring always face down.
The factory method to remove this tricky snap ring is to use picks and other tools (figure 4). When I tried the pick method, I honestly did not have much luck getting the snap ring and the sun gear off the shaft. I preferred using my small tipped snap ring pliers (figure 5). It was easy to spread the snap ring and lift up the sun gear to remove the snap ring and sun gear at the same time.
After the sun gear is out of the way, we must remove the split needle bearing to continue the compounder disassembly (figure 6). Simply use two picks to spread the bearing and slide it over the splines on the shaft.
The factory decided that the bearing is not needed. When we look at the way, the compounder is supported, it becomes easy to see why the needle bearing is not needed.
On one end, there are the two tapered bearings, and on the other end is the bushing in the output shaft, which is supported by the tapered bearings supporting the pinion gear.
Now we can check out the direct clutch, the low clutch, and the clutch.
The direct clutch is pretty straight forward as clutch drums go. It holds a whopping 12 one-sided friction plates. The clutch clearance should be checked before installing the clutch hubs and bearings. Using an angled feeler gauge makes this measurement a breeze (figure 7). Clearance should be .037” – .056” and is adjusted by changing the pressure plate. There is a pressure plate kit from the dealer, part #68004116AA.
LOW CLUTCH DRUM/SPRAG
The low clutch drum has gone through a few growing pains since the 62TE came out. The main issue is the sealing ring groove wear. The drums first came out with rotating sealing rings, and these drums quickly became the weakest link in these transmissions.Turns out, the rotating rings wore into the aluminum grooves built into the drum. Later on, the manufacturer changed the grooves and rings to a tabbed non-rotating sealing ring arrangement. This was a good solution for the groove wear issue, and the rings still had too much side clearance in the grooves.
The aftermarket came up with the best sealing ring/groove wear solution. The aftermarket is taking the new drums and cutting off the existing sealing ring tower and replacing it with a steel sleeve with steel sealing ring grooves. These grooves are tabbed as before and the side clearance on the sealing rings has been reduced to produce a very efficient seal for the ring and the drum (figure 8). The bottom line here is the drum is a part of this rebuild that needs to be figured into every unit.
To check low clearance, we will temporarily install the low clutch pack, and we will use a feeler gauge. The Low clutch clearance should be between .019”- .030” and is adjusted using different thickness snap rings. The sprag and the low clutch pack will be put together on the final assembly. Now we are going to check out the sprag. The sprag has proven to be one of the stronger points of the compounder assembly.
We can identify the top from the bottom by the step on the bottom of the one-way clutch. Also notice the inner race has a black side (which is heat-treated) on top and a plain side on the bottom. There are two offset blind splines, so the race only goes onto the low clutch one way (figure 9).
Now with the sprag disassembled we can see it’s a very traditional sprag assembly with top and bottom washers and oil channel washers that sandwich the sprag element cage to hold the lube oil around the cage. Just remember that when we are assembling the sprag, the black side of the inner race faces up or towards the flat side on the outer race (figure 10).
The compounder has a couple of procedures or checks that we really need to pay attention to when we are going back together.
After removing and replacing the sealing rings, we’ll assemble the empty low clutch drum onto the transfer shaft. We can set the assembly into a hole in the bench or a holding fixture so we can install the bearing retainer cap (figure 11).
Checking the turning torque (see side bar) becomes more critical when we replace hard parts such as gears and low drum housings. We are going to check the turning torque after we install the shim, the gear, and the nut. We can use the factory tool (found online for a little over a hundred dollars) to hold the gear while we torque the nut to a hefty two hundred ft.lbs. (figure 12) Remember, this is a temporary installation, so DO NOT stake the nut! That will happen on the final transmission assembly.
Once the assembly has been properly torqued, we’ll use a dial type inch-pound torque wrench to measure turning torque. Turning torque should be between 8.0 to 18.0 in-lbs. (figure 13). If more than 18.0 in-lbs. choose a larger shim and recheck turning torque. If less than 8.0 in-lbs. choose a smaller shim and recheck turning torque.
After checking the turning torque, remove the nut, the transfer gear, and the shim and set them aside. Now we can turn the assembly over and install the one-way clutch. The one-way clutch rotates counter-clockwise and locks clockwise (figure 14).
Once the sprag is in, let’s install the low clutch pack then the direct drum onto the shaft. The last things we need to do are to install the sun gear and the snap ring.
To finish the assembly, we’ll slide the snap ring over the shaft and down into the sun gear It’s very important that the tabs on the snap ring face towards the sun gear.
The compounder is a small 2-speed transmission that is part of the transfer shaft assembly on the 62TE transmission. The rebuilding of the compounder can go very smoothly when we use the procedures and recommendations described in this article. Always remember the more we know the more we have Fun With Transmissions!
TURNING TORQUE DEFINED
Turning torque is the amount of drag or preload on a tapered roller bearing. The correct amount of preload is determined by the bearing manufacturer. If the bearing is too tight or has too much drag the bearing will over heat and fail prematurely. If the bearing is too loose or has too little drag it may wobble causing uneven wear and premature bearing failure.
Turning torque is measured with a beam type or a dial type torque wrench. The important thing to remember about measuring turning torque is this: The measured turning torque is recorded AFTER the bearing is spinning. We do not measure the turning torque when first starting to rotate the bearing. The reason why is because it takes more force to initially start the bearing rotating than it does to continuously rotate the bearing.