Dana 300 rear output shaft end play

[simple man]

I have finally gotten around to rebuilding my Dana 300 and have run into a problem regarding setting the end play on the rear output shaft. After assembling the shaft and getting an initial end play reading, .005, I added a .003 shim and remeasured the end play and got a .005 reading. So I added another shim and there was no change in the end play reading.

My assumption is that the the inaccuracies in the end play measurements are caused by user error in setting the dial gauge. In setting up and resetting the gauge I may be getting inaccurate readings. In setting the gauge I am trying to place the gauge against the end of the threaded portion of the shaft. However, one questions is could the torquing the yoke on and removing it and replacing it be affecting the output shaft. For example, could I somehow be stretching the shaft?

Is there any trick in setting up the dial gauge?

Another strange problem I have had when installing the yoke is that the yoke will only fit on the shaft in one specific orientation. If the yoke is placed five splines left or right it will not slide all the way onto the shaft. I have tried the yoke on the input shaft and it doesn't have a problem. Any idea of what may be causing this, could the shaft be damaged? Could this be related to the above problem?

Thanks

 

[Lumpy Grits]

After you place and torque the yoke in place. Smack it with a rubber mallet.
Use a sharpy and put a dot on the threaded yoke shaft and measure from that dot each time.
What type of indicator are you using? 'Finger' or 'plunger' type?? If finger type, make sure the 'finger' is screwed on 'tite'.
Good luck,
LG

 

[simple man]

Lumpy, Thanks for your comments on making sure the gauge is set up the same each time.

I have one one more question and this may be a dumb one.

If you have excessive end play, say a total of .007 with a desired play of .003. Does one add an additional .004 shim or remove a .004 shim? The reason I am asking is that, when working on the end play today I was experiencing the same problem of adding shims and having the end play increase. So, I removed some shims and the end play appeared to be removed.

Logically, this does not make sense to me. So I just want to confirm whether in the above example does one add of subtract shims? If the answer is to remove shims can somebody explain why removing shimes decreases end play.

Thanks

 

[simple man]

I think I have figured out the answer to my own question. Adding shims to the shaft moves the yoke further away from the housing therefore allowing more movement between the input and output shaft.

Removing shims reducing the amount of movement therefore reducing the amount of end play.

Is that correct?

Rick

 

[PistolDave]

Are your shims "inboard" of the bearing or "outboard"? They should be "inboard" between the shaft and the bearing, not "outboard" between the bearing and the yoke. You may already be well aware of this, but when I disassembled a D300 that I purchased on craigslist, I found that the PO had installed the shims "outboard", between the bearing and yoke. Just something to keep in mind.

Dave

Also, adding shims will increase endplay, if the shims are in the right location. Removing shims allows the bearings to sit closer to each other, which tightens things up. Torqueing the yoke fully down with shims outboard and no shims inboard in the correct location could damage the bearing races too, by forcing the rollers into the outer races.

 

[Lumpy Grits]

It depends on where the shims are located on the shaft.
This may answer some questions.....
https://www.youtube.com/watch?v=cmarMQXASh4

LG

 

[simple man]

Yes, the shims are inboard of the bearings.

My initial problem was caused by my assumptions that one would increase the size of the shims to reduce the amount of end play. Like one would do in setting end play in a rear end.

Once it hit me that the transfer case is just the opposite I should be able to get back on track.

Thanks

 

[Ultrunner]

I’m having similar issues. I have verified the rear output shaft is assembled correctly, but am having a hell of a time with the end play. I’ve begun with the original number of shins (3) and had absolutely no endplay. I added two more and still nothing. I’ve ensured all bolts and yoke but are properly torqued prior to checking. The shaft will turn, but I can’t seem to get any end play.

Does it seem right that I would need to add so many shims? I’m up to six.