range synchro problems

I have been having a difficult time with the range synchro. It was bad on my 15 speed rto15715 when it was pulled apart for other problems. Now going back together I have had nothing but problems. I think I have taken a lot of bad advice from different mechanics that all said they knew what they were doing and all seem to be wrong.

Regardless, I have been trying to get the trans back together and it seems that the range synchro just won't mesh properly. It is hung between high and low. I also feel like the deep reduction is having problems engaging and disengaging.

The last time I put it together I followed the eaton book which has pictures that are not the same as what I have but it was the manual they gave me... everything was working well until I put the yoke on and tightened it down. It became extremely hard to turn. I know this could be a result of the range synchro being hung between high and low or the timing being off.

The latest assembly I timed it by using a straight edge on the gears to make sure they are parallel to the shaft and I tried using shop air to move the range synchro. It doesn't even look straight and it doesn't engage the aux drive gear or the low range gear on the back side. It just moves a 1/4in or so with no positive engagement.

I have done in-frames, rears, auto trans, four wheeler manual trans, and heavy equipment repair for 15 years off and on, so I am no fool when it comes to doing the job or listening to a more experienced person tell me how to do it.

I am at my end with this thing. I spent 1000 in parts to fix it and paid another 1000 to have it pulled and put back in because I recently had back surgery and don't have the strength to do myself. There must be someone here who can give me some good dependable advice on what I am doing wrong....

 

I have the trans out of the truck to replace a few other things. I am setting it up with the front input shaft facing the ground so all i have to do is line everything on the aux gear then drop the case over and bolt down. it is not that bad to do just cant seem to make it work. there is something stupid i am missing.

I have been told two different ways of timing. the one like the eaton book says with a straight edge and the other following the curve of the gear. I don't think that I can follow the curve because it sets the shaft a few degrees off center? I feel strongly that the issue is in the new range synchro. I know eaton issued a revised part and i checked inforanger says it is right.

What is up with the literature I literally have books for the trans with the wrong pictures and other books with different parts diagrams. There doesn't seem to be a consistent source of what to do and what belongs...

Thanks for the reply if you have any other suggestions please let me know.