**PLEASE READ ENTIRE PROCEDURE BEFORE ATTEMPTING TO DETERMINE WHAT YOU NEED TO COMPLETE IT**
About a month ago, it was finally time to replace my noisy throwout and pilot bearings in my 2006 TJ. Upon searching the web for possible guides on removing the Jeep's 6-speed, I could not find any one thread that shed alot of light on the procedure. So, while I kind of guessed through the process, I snapped alot of photos so that others could learn from my experience and possibly use it to help with their own. This thread will include the removal and reinstallation of the NSG-370 6 speed transmission, flywheel, clutch assembly, throwout bearing, realease lever, release lever pivot, and pilot bearing. Hopefully, this thread will help you guys who are considering doing the job yourselves!
A special note to read before continuing:
I am in no way a qualified mechanic. I am however comfortable with complex mechanical procedures (replacing a head gasket or differential regears). Even so, I advise to everyone reading the thread that all of the procedures used be taken lightly. I do not recommend anybody who is not comfortable with such procedures attempt the following. The transmission/ transfer case are heavy, expensive, and can be hard to remove. Using some of the methods described by myself in this thread can lead to damage of both the vehicle or yourself. Anyone who will be using this thread as a guide acknowledges that the author is not responsible for any injury or damage that results from performing the procedure. Be careful, go slow, and exercise patience.
Specs on the Jeep that may relate to the procedure:
-Daystar polyurethane transmission mount
-stock skid plate/ .5" skid plate spacer
-Currie (no lift) polyurethane motor mounts
-Advanced Adapters Transfer case linkage relocation bracket
-3" lift+ 31's during procedure
Alright lets begin,
-First thing I did was shoot all of the bolts connecting the engine block, transmission, and dust cover with WD-40. This was allowed to soak for 3-4 hours before proceeding.
-Next, I disconnected the (-) Negative terminal on the battery and placed all four corners of the Jeep on jack stands. I made sure to place the jack stands on the axle tubes as close to the spring perches as possible.
I use socks to cover the top of my jack stands as I don't like the idea of metal on metal contacts supporting the entire weight of the Jeep for long hours.
It is important to determine how high you will need to elevate the Jeep before you begin any other procedure. I planned to pull the transmission out from underneath mine, so I had to raise it a considerable amount. Even while resting on a low profile creeper (about 2.5"-3" off the ground from the bottom of the transmission) the transmission's shift tower still ended up being about 21" tall.
This must be able to clear the bottom of the frame rails if you plan on removing the tranny from under the vehicle. It will be even taller if you roll the transmission out while on a floor jack mounted transmission adapter (with mine it was approx. 32" tall
). However, if you are fine with leaving the transmission under the vehicle while you work, you could probably get away with leaving the bottom of the frame rails at 20". Just make sure to measure a few times before going on!
-OPTIONAL: I removed the driver's side fender, as well as the exhaust downpipe/cats/muffler. This was done as I was also working on the engine side of things, so it is not required. However, dropping the exhaust did make working on the transmission much easier (gives you a lot more room to work). I suppose you could remove the transmission with the downpipe in place, but it seems like it may cause clearance issues down the line.
-Shift the transmission into neutral then remove the shifter from inside the Jeep. The shift boot connects to the center console by 4 plastic clips near it's corners, and must be removed first. This was done by using a flathead screwdriver to pry it up and free. Be careful, as the plastic tends to bend easily. With the shift boot pulled up and out of the way (still on the shifter however) you can pull the rubber cover from the shift lever bushing. This will exposed a bolt that connects the shift lever to the shift tower on the transmission (see photo).
-I used a T-45 star bit to remove it. Then I simply pulled the shift lever from the shift stub, with the shift boot still attached to it.
-The next thing I did was unbolt the slave cylinder from the transmission bellhousing (driver's side). It is only secured by two nuts. Once free, I simply zip tied it to the fuel lines to make sure it was out of the way.
-Remove the starter from the passenger side of the transmission bellhousing
-Remove the rear drive shaft making sure to make alignment marks to maintain itís balance on installation.
-Unbolt the 4 nuts on the bottom of the skid plate securing the transmission bushing to the skid plate. As you may have noticed already, your going to have a lot of nuts/ bolts laying around as you take things apart. I highly recommend you organize these so none are lost or misused during installation.
-I then supported the transmission in front of the skid plate using an OEM bottle jack out of a late model Toyota Tacoma. Since the Jeep was raised so high on the jack stands, I had to stack some bricks underneath for it to reach. Bricks have a tendency to crack under jacks so I used layers of old shirts in an attempt to more evenly distribute the weight. Worked out perfectly with no cracked bricks!
*On a special side note here: I honestly recommend you all get one of these for your bottle jack needs. It blows the one that came with the Jeep out of the water in terms of smoothness and lifting range! Plus is has what appears to be a polyurethane tip so as not to mare up the metal it contacts. Best payment I've ever received for doing an oil change
-After the transmission has been supported, I unbolted the skid plate. As many of you know it can be kind of heavy depending of which one you're running. Using a floor jack to lower it makes it much easier than trying to awkwardly bench the thing when your by yourself.
-With the skid plate out of the way, I removed the front driveshaft unbolting the 4 bolts at each end to remove it completely. I then removed the transmission bushing, as it created a clearance issue with my transmission jack setup. It is held in place by 4 nuts, shown circled in red (looking from rear to front of vehicle). If you left your exhaust downpipe on the vehicle, you would also have to remove the nuts circled in blue, as that bracket supports the downpipe at it's rear. I left mine in place as my exhaust was removed earlier.
-I then made sure the transfer case was in 4-HI and disconnected my transfer case linkage at the transfer case shifter. This was done by soaking the bushing in WD-40 and using a pair of channel lock pliers to squeeze the bushing out from the shifter. The linkage end/bushing circled in blue was inserted into the end of the transfer case which is pointed to in green. I have a linkage relocation bracket to isolate my linkage from the tub. If you do not, and have the stock linkage bracket, (which mounts to the tub and would be in the area circled in red) I assume that must also be removed.
-At this point the only things connecting the transmission to the rest of the Jeep should be the engine, wiring harness, and breather tube. Once this is confirmed, position a transmission jack of some sort under the transmission bracket (or where it used to bolt up). I had used a P.O.S. transmission adapter for a floor jack. The problem I ran into was how high the adapter was, but this will be addressed.
In this picture, I had positioned the jack too far forward, as I figured out when the entire thing tried to take a dive backwards (that's why you strap/ chain the transmission to the jack). When I do this again, I will be positioning the jack a few more inches towards the transfer case...
-Once the transmission jack was under the transmission, I raised it enough to relieve the support jack (That Tacoma bottle jack I used). Then I threw a ratchet strap over the top of the tranny and connected each end to the sides of the tranny adapter and tightened the whole thing up. This will help hold the transmission onto the jack just in case it is misbalanced to prevent your tranny from falling a few feet onto your garage floor. So make sure you strap it down!! Just be sure to run the straps underneath the wiring harness so that this can be easily removed later.
-With the tranny jack now supporting, I removed the bottle jack.
-I lowered the floorjack/ tranny jack until the transmission had moved about 10-15 degrees downward to expose the wiring harness that runs across the top on the transmission.
-I disconnected the CPS sensor's electrical connector, then removed it from the bellhousing (1 bolt). After this I removed all the electrical connectors, the breather tube, and the wire harness mounts from the transmission.
Referring to the picture above: The electrical connections are circled in red with the CPS at the front, the wire harness mounts are circled in yellow, and the breather tube connection is in blue
-Now came the time to unbolt the transmission from the engine block. Before doing so, it's very important to make sure that the transmission is secured to the jack by either a safety chain or strap over the top. If not, it can topple over off of the jack once unbolted, possibly resulting in damage or injury. The transmission is secured to the block by two E12 torx bolts on top, and 2 16mm bolts on the sides. The dust cover or inspection plate must also be unbolted from the transmission, as it is a one piece design on the 6 speed that cannot be removed until the flywheel is taken off.
-To access the two E12 bolts, I lowered the transfer case end of the transmission as much as I could (ended up being something like 25-30 degrees). Be careful here not to tear the rubber grommet that surrounds the shift stub as it is pulled out.
-The bolt on the driver's side was accessed using 9" of straight extensions
-The passenger's side bolt was accessed using 2 ft of straight extensions
These top bolts came out easily for me, most likely because I had soaked each in WD-40 before I even started. However, they were replaced with hex head bolts at installation in order to reduce the possibility of stripping the heads in the future.
-With the top two E12's removed, I jacked the transmission back up a little to about 10 degrees. Then using a 16mm socket, removed the last two bolts securing the engine block to the bellhousing (their position circled in red in the following picture).
-I removed the screws/ bolts securing the dust cover to the bellhousing (circled in green on above picture).
-Now, the transmission is completely unbolted from the engine, and the wiring
harness has been disconnected. Once again, I lowered the tranny to a moderate angle, this time slowly pulling the transmission towards the rear of the Jeep. Once the guide pins were cleared, I raised the transmission up to nearly parallel to the ground, and pulled it out the rest of the way until the input shaft was clear of the pressure plate.
Next came the annoying part... upon lowering the transmission to the bottom of the jack's lifting range, I discovered that the shift tower would not clear the bottom of my frame rails
. Even at the bottom of the lift range, the adapter was so tall that the jack was still a good 15 inches above the ground. In order to get the transmission out from underneath the Jeep, I determined I would lower the tranny onto a creeper (you do not need to do this to access the flywheel, throwout bearing, and clutch). If you have someone to help you, I'm sure the transmission could be lifted from the jack onto the creeper, but I was by myself and that thing is pretty heavy. So, I used a pair of ratchet straps to slowly work the transmission down to the creeper's height. I DO NOT RECOMMEND THIS PROCESS TO ANYONE. Although it did work without damaging my transmission, there is a large possibility of damage or injury that could result from this.
-With the transmission at the lowest height my jack would allow, I ran a ratchet strap underneath each end of the transmission/ transfer case.
-These photos showed what the setup looked like once it reached the height of the creeper. Beginning at the rear, it was done by keeping one end tightened, then loosening the opposite while supporting that end's weight by hand (as the ratchet strap no longer does once it has been loosened). Then I would lower it by hand about 5 inches, and re-tighten the strap to support that end at the new lower height. The process was repeated at the opposite end, and this continued until the entire assembly rested onto the creeper. This worked as the end that had the tight strap was carrying a lot of the transmission's weight as the opposite end was lowered by hand. Once again, don't try it. I'm only documenting it to show how I got the transmission from adapter height down to the creeper height.
-When I pulled the transmission out from underneath the Jeep, I removed the release lever retaining clip that holds the release lever to the release lever pivot (on the passenger side inside the bellhousing). This allowed me to remove the release lever and throwout bearing.
Retaining clip seen on left side of release lever
-Using a 19mm deepwell socket I uninstalled the old pivot
-I proceeded to clean and degrease the transmission while I had it out, making sure to seal off the electrical connectors and breather tube beforehand.
-Once dried, I installed the new pivot for the release lever. In the picture I am demonstrating how the retaining clip attaches to the pivot behind the release lever.
-Next I removed the old throwout bearing, cleaned the release lever, and installed my new bearing. I went with a National throwout bearing after reading good reviews on it, and it's worked well so far. The throwout bearing has two springs that hold it on the release lever. To attach them, just angle the bearing into the lever as shown in the photo below, then use a flathead screwdriver to pull the end of the spring over the lever. Do this to each side and the bearing will be secured. Be sure to apply high temperature grease to the spots where the bearing contacts the release lever!
-With the throwout bearing on the release lever, I applied high temperature grease to the release pivot, the input shaft splines, the machined surface of the throwout bearing, and on the input shaft where the throwout bearing would slide. Then I made sure my release lever was lined up correctly (using the throwout bearing as reference it is longer on one side than the other) and slid the assembly back onto the input shaft. Reattach the lever to the pivot using the new retaining clip
-Now back to the clutch and flywheel, I supported the clutch disc using the clutch alignment tool before unbolting anything. Be sure to use gloves and avoid spraying the clutch dust into the air, it's bad stuff to breathe.
-With the clutch disc supported, I used a cheater pipe rammed between my flywheel's ring gear and my frame to keep the assembly from turning as I loosened the bolts. The yellow refers to the position of the pipe as I was uninstalling everything (The red pipe is in position for when tightening the bolts)
-Make sure to mark the clutch and flywheel somehow to ensure they are installed in the same alignment in order to maintain their balance.
-With the assembly secured by the cheater pipe, I began to loosen the 6 13mm bolts that hold the pressure plate to the flywheel. I went in a criss-cross pattern only turning each bolt a 1/4 turn at a time because the pressure plate is under pressure (it's a big spring) and can warp if the bolts are removed unevenly. Once I felt all the spring pressure was released, I removed all but one bolt at the top. This last bolt was removed once I had a good hold on the pressure plate, as once it's all unbolted, the pressure plate will want to just fall off. With pressure plate out of the way the clutch disc was also pulled off with the clutch alignment tool. Inspect the rivets on the clutch disc. These should not protrude above the friction material, and if they do can damage your pressure plate and flywheel. If your pressure plate shows grooving or marks from rivets grinding onto it, it will need to be replaced. The same goes for the surface of the flywheel (although if minor, machining might be able to be used). Iím not replacing my clutch disc at this time because it has a good layer of material left above the height of the rivets, but if youíve already got it out, you may as well replace it if you donít plan on taking everything apart any time soon (I am).
-Now the flywheel should be all that's left. It's not required to remove the flywheel if you're replacing the pilot bearing or only replacing the clutch, you can leave the flywheel on if the surface looks good. It's nice to get it resurfaced, but that was money I didn't want to spend. I ended up sanding mine down for about 10 minutes with some 150 grit and called it good.