- - Dana 300 Rebuild
07-08-2011 08:54 PM
Dana 300 Rebuild
While waiting to acquire another T 176 transmission I decided to rebuild my Dana 300. It was not in that bad of shape build the timing was right. I ordered the Novak Master Rebuild Kit and it is pretty good; however, I got two wrong bearings in it. They are sending one of them; however, I found the other one after I spoke with them about the first. I am sure they will love me after the next phone call. Good point to remember: always go through the kit and check (then recheck) everything. So far the rebuild is going pretty well. I have taken lots of photos in order to help myself put everything back together. I will try to document all that I have done so far.
To remove the yokes you will need a 1 1/8" socket. An impact gun makes this easy work. A two or three jaw puller will remove the yokes.
Next loosen the six bolts holding the Input Shaft Support. (Allen Head) The Support is a tight fit and will require some careful prying to get it loose. There are two places machined in the support for this. When you remove the support the input shaft, input shaft bearing and the rear output shaft gear will come out also. They are all held on the input shaft with a snap ring.
07-08-2011 09:10 PM
The next step is to loosen the bolts holding the Rear Bearing Cap and the Front Bearing Cap. Both caps will require some help with a plastic hammer or something to get them off. You could also use some sort of puller. Before removing the caps get a wooden dowel about 1 inch in diameter and 6 inches in length. Remove the lock plate bolt and lock plate. Use the wooden dowel to drive out the intermediate gear shaft. The dowel will replace the gear shaft and prevent the needle bearings from falling inside the case. Now with the bottom cover removed you can reach inside the case and hold the intermediate gear while you remove the wooden dowel. The needle bearings and 3 bearing spacers will fall out. One of the spacers is wider than the other two. This one goes inside the gear between the sets of needle bearings. The other two go on the outside of the needle bearings. There are also two thrust washers that will fall into the case. Put all of these parts together in a large zip lock bag. Now you can remove the bearing caps.
07-08-2011 09:26 PM
Next comes the Output shaft shift forks. Look in the middle of the case where the intermediate gear used to be located. The shift forks are attached to the shift rods with allen head set screws. Remove the set screws with a 3/8 inch drive socket. You do not want to strip these screws. Prior to removing the Front bearing cap you will have to remove the 4wd indicator and the plug next to it. This will help with the removal of the shift rods. Under each rod is a poppet ball and spring. These will jump out of the bearing cap when you remove the shift rods. I just placed my hand over the holes and caught them. To remove the shift rods you will have to pull and twist. They come out pretty easy and should not bind. If they do then first check the shift fork and make sure the fork. The fork tends to bind on the shift rods. Do not force the shift rods out.
07-08-2011 09:40 PM
Looking good so far!
07-08-2011 09:41 PM
Yes it does. Can't wait to see more.
07-08-2011 09:41 PM
Now you can remove the shift forks. Next remove the Cover Plate from the rear of the case. Do not damage the shims under the cover. These set the end play. Tie them together and save them for later. The bearing race in the case is not a press fit and should come out pretty easy. The bearings on the front output shaft are pressed on and have to be removed prior to getting the shaft and gears out of the case. A press works great for this. I am sure a bearing puller would work as well. When you remove the rear bearing you can remove the clutch gear and the clutch sleeve. Now the rest of the gears and shaft can be removed from the case. The front bearing then can be removed.
07-08-2011 09:49 PM
The Rear Output shaft comes out after you have removed the rear bearing cap. Make sure to keep track of the shims located between the shoulder of the shaft and the rear bearing. These set the end play. The Rear output shaft bearing must be pressed off and then you can remove the shaft and the clutch gear.
07-08-2011 09:58 PM
Now you have an empty dirty case. It is heavy. Time for some sandblasting and paint. I used Eastwood's Epoxy Primer. It is pretty good. I top coated the case with Hammered Black and the Bearing Caps with Hammered Silver. Just a few notes on the Front Bearing Cap. If you plan to remove the shift interlock pins you have to destroy the aluminum plugs on the bearing cap. I used a 1/4 NPT tap and then used socket plugs. I also did the same thing with the vent plug. It was loose so no better time than the present. Time to remove the races. This is where the press shines. It took all of 15 minutes to remove all seals and races from the bearing caps. There are two in the rear bearing cap and one in the front bearing cap. The race in the case should come out without a press.
07-08-2011 09:59 PM
07-08-2011 10:05 PM
I ordered a Novak aluminum bottom cover which is pretty nice. I am wondering if I should use the paper gasket that came with the rebuild kit or just use an anaerobic sealant like Permatex 518? Any ideas? Also the Input Shaft Bearing sent by Novak is the right size; however, it has a groove on the outside of the bearing for a locator ring. (Same bearing as the T 176 uses on the input shaft) I am wondering if the groove will cause any problems. The bearing is pressed in the Input Shaft Support and the groove will be covered by the shaft support. I hate to have to wait several more days for Novak to send the correct one. Any ideas?
07-08-2011 10:09 PM
When I replaced the fluid in my 300 I used the paper filter, sealed both sides but still had a small drip from the corner. I would just use permetex.
07-08-2011 11:02 PM
Thanks for the write-up. Bookmarked!
07-10-2011 09:54 AM
Question for all. In the kit from Novak they sent me the wrong input shaft bearing. It is the same bearing that the T 176 uses (6209) with the groove for the locating snap ring on the outside of the bearing. The one that the Dana 300 uses does not have the groove for the locating snap ring. Both bearings are the same size. Do you think that it would hurt to use the new (wrong) bearing? The input shaft bearing is pressed into the input shaft support. The bearing goes into the support flush and is secured with an internal snap ring. The groove will be concealed inside the support. I know I should call Novak and have them send another; however, I have already done this once with the rear output shaft bearing. I hate to wait another three or four days for this bearing. I can get one locally put it is the NAPA brand and I have not heard anything good about those bearings. What do you think?
07-10-2011 02:50 PM
The groove won't make a difference,I would use it. But it will be on your mind always,tucked back there.....nagging.... but it would be fine. You are doing a top notch rebuild it looks like, be patient and wait the excruciating days for the correct part,you will be more satisfied in the end.
Novaks site clearly calls for no gasket,sealant only. Nice work!!
07-10-2011 03:22 PM
I was hoping to find one locally today but no such luck. I guess I will call Novak and get the one without the groove. Yea I prefer sealant only because it usually makes for a leak proof fit. (with the right prep) Paper gaskets always seem to soak up oil and then leak.