Warn OD shift rail

I have a warn OD which has the shift rail coming out the front of the case (see pic OD01 below).

Most OD's I see have the shift rail coming out the rear of the case (see attached link). http://www.public.asu.edu/~grover/willys/od.html

The AA catalog shows an exploded view of the saturn OD with the shift rail coming out the rear.

Is the shift rail location any indication of particular differences between the OD's? If so, what are those differences? What are the advantages/disadvantages to the front or rear shift rail? What is the reason for the 2 different shift rail locations? There must be some kind of engineering rational behind it.

 

Herm can tell you for sure
my understanding was the original ODs were all front shift
Dana/Spicer made a change to the case of the transfer case
the front shift OD would no longer work, clearance issues
the rear shift OD was born
I think herm talks about it on his site

 

Thanks Jim. You were right. Herm talks about it in his "history of the overdrives" section. I wonder what year dana/spicer changed the casting on the model 18 transfer case to warrant a change in the location of the shift rail? I'd also love to know what that change was? I havent yet bolted my front shift OD to my transfer case. hopefully i dont have any problems.

 

I think it had to do with the front shift (lever) housing on the t/case, not sure.
this is why it pays to be attentative (alert) when buying/bidding on an OD.
some folks get caught up in OD fever and don't pay attention to front/rear shift
the front shifts are worth less $$ because of this IMO

 

worst comes to worst, i'll modify the front shift to work. a small obstacle to have overdrive. i'll check with herm to find out exactly what the difference is in the T case that warrants the OD shift rail changes.
by the way, herm charges the same price for a front or rear shift rebuilt Warn OD, but i guess the rear shift would work with either T case.

 

Wow, that is an old thread. I thought the topic looked fimilair. Shortly after i posted this thread, i read another thread talking of the dana 18 housing differences.

see this pic:
http://img.photobucket.com/albums/v711/mudweisercj5/DSC00075.jpg

you can clearly see the difference in the casting on the top of the transfer cases. warn originally offered only a front shift OD and later in production, made only a rear shift OD. you can see in the picture how the linkage for the front shift OD would interfere with the casting on the large hole dana 18. A rear shift OD would work with either case (and is all that Saturn now offers), but the front shift unit would work only with the small hole case.
The above pic clearly indicates exactly what change took place in the casting of the dana 18.
This is definetly something to consider in addition to the spline/tooth counts if you come across an old Warn OD.

 

Would the easiest way to differentiate the front shift compatable t-case be to count the shift levers? Dual lever D-18 T-case being the earlier type and compatable with the forward shift overdrive? Or were there mods to the small hole dual lever T-Case's to make them single lever, and if that is so is there some other "Spotters guide" easy way to determine compatability?
I am also thinking of an OD to help the streetability of my 134F/4.27 CJ5

 

Dabblin
the number of shift levers doesn't matter
it's the reinforcement in the case at the rear
study the photo above again; look where the OD would bolt up
the small hole case is fairly flat where the shift rail would come forward
the large hole case has a "hump" which blocks access for the shift rail

 

Yeah I can see the reinforced case area that would make the forward projecting OD lever a no go on the wide holed case. I was thinking that from the drivers seat the number of levers might imply the type of case that was residing out of sight under the floor pan. From the pic it is hard to tell if the single vs dual lever setup is interchangable. I have a 67 cj and if anyone has a forward shifting OD and doesn't need the worthless pos I'd be willing to try bolting it up to my rig??

 

This may be helpful.....

http://www.brandondempster.com/documents/saturnOD