I put together a few photos to show what needs to be done to reclock the tail shaft housing on a NP229 transfer case so that the speedometer cable enters the case in the same spot as it does on a 119/129/128 transfer case.
The only Eagle case I have taken apart is my 128. I was originally going to use the back have of the 128 case on the front half of the 229 case so the tail shaft housing would bolt up. It's hard to explain but there is one rail inside the 128 for the 2wd/4wd selector. In the 229 there are two rails. One for 2wd/4wd and one for the low range. I've read you can put the Eagles back case on the 229 however the hole in my 128 case, where the low range rail would need to fit, was too small and would have been too difficult to enlarge.
Here's a pic of a 229 on top and 128 on the bottom.
The red circles are where the speedometer cable enters the transfer case. I didn't try it but I've read that if the 229 TC is installed as is, there will be problems with the cable hitting the floor. The tail shaft housings themselves are identical between the Eagles TC's to the 229. The only difference is where the vent is installed from the factory. You can see the 229 vent circled in yellow and where it would be on an Eagle TC in purple. I don't think it would make a big difference if a 229 housing was installed without moving the vent to the Eagle's location but it would be fairly easy to move.
229
128
Here's a pic of the 128 with the tail shaft housing removed.
Circled in red is where the bolts for the tail shaft housing thread into for the Eagle location. The yellow circles are just holes, no threads. That is where the 229 case holes would be. Notice one hole is missing by the arrow. On both of the 229 cases I have, they only had one set of holes where you see the yellow circles. I drilled new holes where the red circles are and then tapped them. There is a boss for the holes. I split the case to keep shards from getting into the TC. Actually you could try to tape off the holes that would let shavings into the case and not drill deep enough to go through the boss. It would require a bottom tap since you will be tapping a blind hole. It is important to get the holes in the right spot. If you don't feel confident, it would be quite easy for a competent machinist.
Here's a couple of pics of the vent on the housing. This is the 229 location. If you had to use the 229 housing you could plug the one hole and drill a new hole in the proper location.
It sounds difficult, but once you have it in front of you, it will make sense. The 229 swap is not a bolt in and go. It does require some minor fab work to be done CORRECTLY. Anyone can slap stuff together, but if you want something to work correctly, without trouble, it is better to spend a little more time to do it right. Hope this makes sense.
Topic: Reclocking NP229 Tail housing (Read 8747 times)