Rebuilding the flipped Dana 300 Transfer Case with Teralow Gears

At this point, the transfer case has been stripped of all parts and thoroughly cleaned. Time to rebuild and flip it.

Again, steps that are required for the Tera 4 to 1 and not the flip kit have RED text.

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The old case was looking tired. It was dirty and the paint started coming off when I cleaned it. The case is steel, so a repaint was in order to keep rust at bay. Here, I have primed the case.		Bright, isn't it? I chose not to repaint the case black so if any leaks develop, I can see them easier. I went to the hardware store to buy gray paint but this color was right next to it. It is a close match to the factory blue of my TJ.		This shows the differences between the stock D300 gears (top row) and the Teralow D300 gears (bottom row). The Teralow kit also includes 2 additional gears (not shown) to replace the stock large gears. Tera says their new large gears are cut slightly different to reduce gear noise.
These are the components of the Downeast Offroad flip kit. The included shifters are from an Atlas II tcase. Not shown, but included in the kit, is a new set of seals for the D300.		This is the Dana 300 clocking ring made by Cory Morgan. It has 5 positions for clocking the D300. It is not required to mount the D300 but I wanted more clearance.		Time to start reassembling the Dana 300. The first step is to start reassembling the front outpost shaft. This is done by putting the new Teralow gear on the shaft and then pressing the bearing in place. I used my Harbor Freight 12 ton shop press for this.
Next, the assembles shaft is placed in the case and the large gear and clutch sleeve are added to the front output shaft assembly.		I then used my aluminum block to get the front bearing started on the shaft. To get the bearing on the rest of the way, I used the old bearing to press it on the rest of the way.		Now the assembly of the rear output shaft is started. The new large Teralow gear is placed inside the case and the output shaft is fed through the gear. In this pic, I have the thrust washer (next to the gear) and bearing in place, ready to press on.
The bearing is being pressed in to place on the rear output shaft. This is my $5 Loews hardware store bearing press adapter. It is made out of caps, tubes, and couplers from the plumbing department.		Starting to rebuild the input shaft assembly. Here, I am pressing the bearing into the input shaft housing. The bearing actually sits below the lip of the housing so I used the old bearing (at right) to finish pressing the new bearing in.		The bearing is pressed in place and the snap ring is installed. With the flip kit, since this housing is normally modified which eliminates the forward seal, this bearing is replaced with a sealed bearing. It becomes the forward seal.
The input shaft has been inserted in the bearing. I used a plastic mallet to knock it in to the bearing.		The forward oil seal has been pressed in to the input shaft housing. With the flip kit, this housing would be cut down where it starts to angle up (arrow), but since I am using the clocking ring, I didn't need to modify it.		The new Tera gear is being pressed on the the input shaft. Then a snap ring was installed to keep the gear in place. The original gear would slip back on, but the new Tera gear was a little tighter so I pressed it back on.
The clutch sleeve was installed on the rear output shaft and gear and then the input shaft assembly was slid in to the case.		I then torqued the allen head bolts that retain the input shaft assembly to the case.		Here, I am pressing the forward bearing race in to the freshly painted housing. I used the old race to finish seating the new race in place.
And now the rear bearing race is going in. Notice my high dollar race pressing adapter. Again, a plumbing implement from the local hardware store.		Rear bearing and seal are installed. I used the same tool as in the previous image to seat the rear seal.		Rear output housing is bolted in place. I seated the rear bearing on the output shaft by placing the old output yoke on the shaft and tapping it in with a plastic mallet.
The new CV style rear output yoke (Spicer part # 2-4-4341) has been installed and torqued down. Here I am checking the end play of the output shaft. It needs to be within 0.002 and 0.005 inches. Mine was .005 on the first try.		Next, I moved on to the front output shaft. Here, I have tapped the forward bearing race in to the case. It is important that no gasket sealer get in that slot on the left side. It feeds oil to the back side of the bearing via a channel in the cap.		The bearing race for the forward bearing on the front output shaft is being pressed in to place. Again, I used the old race to finish seating the new race. It is not shown here, but the front seal has also been installed in the housing.
Then the housing is bolted and torqued down to the case. I have mounted the dial indicator to check the end play of the shaft. As with the rear shaft, it must be between .002" and .005". This is achieved by placing shims between the case and the cap shown in the next picture. This must be done because of the complete rebuild.		The end cap in torqued in place. It took two of the shims between this cap and the case to get a .004" reading on the dial indicator. With the D300 flip kit, these shims are not touched and the measurements taken in the previous step are not necessary.		Forward output shaft and gears installed in the case.
These are the parts of the intermediate gear. They include the gear, the spacers, shaft, and the needle bearings.		The needle bearings and spacers are held in place in the intermediate gear with grease until the intermediate shaft can be pressed through from outside the case.		There are two of these thrust washers in the case on either side of where the intermediate shaft goes through the case. The intermediate gear will fit between them.
Here, I am trial fitting the gear in place. The rear output shaft shift fork still has to be installed before this gear is secured in place. The intermediate gear must be sitting on the bottom of the case to make enough room to slip the fork in place.		The new shift fork for rear wheel drive is now in place. This is a part supplied in the flip kit		Now, the intermediate shaft is slipped in to the case and through the intermediate gear. There is an o-ring on this shaft to prevent leakage.
The shaft is then held in place with this plate and bolt.		This aluminum adapter plate is also part of the flip kit. It holds the shift rods. It is has been sealed to the case with gasket sealant and is held in place by the two bolts until the sealant is cured.		This is one of the shorter of the Dana factory shift forks. It will become the shift fork for front wheel drive. The new gray rub pads are supplied in the flip kit.
The shift rods and forks are installed. The mode detents are visible in the rods, They denote high, neutral, and low ranges. These shift rods are part of the flip kit.		Here, the poppet balls for the shift rods are installed. You can see one in the right hole. On top of the balls are two springs as seen in the left hole.		The original D300 cover is now installed over the flip kit adapter. The tabs welded on the end of the shift rods keep the transfer case from being shifted in to front wheel low range and rear wheel high range at the same time and vice versa.
This is the shift rod cover. It is another part of the DEO flip kit. At the top left of the picture is the new vent fitting for the case vent line. Unfortunately, when I clock the tcase, the hose connected to it will hit the body so I need to find a 90 degree fitting to replace it.		I have installed the first part of the shifter assembly. The flip kit includes the complete shifter assembly from an Atlas II transfer case.		The rest of the shifter assembly is trial fitted. It will be removed to install the transfer case in the TJ.
The new vent fitting. I used the original fitting plus a 90 degree fitting.		All done. Front view of the completed flipped Dana 300 transfer case. I'll install the clocking ring when I install it in the Jeep.		Rear view. Time to install it in my TJ...

Installing the Dana 300 in my TJ

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