Differences in Oil Guides in our transmissions

[doesitonall4rs]

Hey guys, long story short, I blew my trans, which I found has been rebuilt sometime in its life. (its a 91 AWD Transmission) I purchased a used trans (Also a 91 AWD), when I went to take out the diff I found out that the intermediate shaft and input shaft had excessive play (On the used trans). So I decided to freshen up the roller bearings.

Anyways upon the dis-assembly of the transmissions I found out that the used trans has 1 oil guide and the trans I broke has 2 oil guides. What is the difference? Should I swap to 2 oil guides on this used trans or just leave it how it is? Is there benefits to one over the other?

Any help is greatly appreciated, thank you!

 

[twicks69]

Hey guys, long story short, I blew my trans, which I found has been rebuilt sometime in its life. (its a 91 AWD Transmission) I purchased a used trans (Also a 91 AWD), when I went to take out the diff I found out that the intermediate shaft and input shaft had excessive play (On the used trans). So I decided to freshen up the roller bearings.

Anyways upon the dis-assembly of the transmissions I found out that the used trans has 1 oil guide and the trans I broke has 2 oil guides. What is the difference? Should I swap to 2 oil guides on this used trans or just leave it how it is? Is there benefits to one over the other?

Any help is greatly appreciated, thank you!

1990-Early 1991 transmissions used two oil guides, and for mid-1991-later, the trans was revised to a single oil guide. If you look closely, the later model transmission case intermediate gear cluster section should not have the casting inside the case to hold the smaller oil guide.

It really isn't a life-or-death thing to add or remove the small oil guide. Run the better condition case, and use the oil guides that match to the case being used.

 

[doesitonall4rs]

Believe it or not before you even posted, I wanted to PM you about this, I have been reading a lot of your posts in the last couple of days due to me doing a lot of research on transmission rebuilds and such .

The 1st thing I did notice is that it was missing that casting for the 2nd oil guide.

Also I am curious how can you visually tell the differences between 3rd and 4th gear set between the 90-early 91 and the late 91 to 92-5 since that year has the "best" gear set.

I pulled both of my transmissions apart and pressed all the gears off, everything looks almost identical between the two transmissions minus the oil guides. Just want to make sure I make the strongest combo of parts that I can.

 

[twicks69]

Believe it or not before you even posted, I wanted to PM you about this, I have been reading a lot of your posts in the last couple of days due to me doing a lot of research on transmission rebuilds and such .

The 1st thing I did notice is that it was missing that casting for the 2nd oil guide.

Also I am curious how can you visually tell the differences between 3rd and 4th gear set between the 90-early 91 and the late 91 to 92-5 since that year has the "best" gear set.

I pulled both of my transmissions apart and pressed all the gears off, everything looks almost identical between the two transmissions minus the oil guides. Just want to make sure I make the strongest combo of parts that I can.

The 1990-early 1991 differences that are obvious are:
*Small diameter 5th/Reverse synchros and hub/slider assembly.
*5th gear cover with wide outer corner edging by 5th/Rev hub/slider assembly w/ part number "MD735345" stamped inside in the casting.
*Wide 5th cover oil guide.
*2x black plastic oil guides (one thin/small one, one large/wide one).
*3rd gear on input shaft has no markings in the gear teeth.
*4th gear on input shaft has 2 markings evenly spaced in the middle of the gear teeth.
*2nd gear is a single synchro gear on the intermediate shaft with short dog engagement teeth.
*1st gear has a very thin backside and is cast with the marking "65" on the backside; it also has short dog engagement teeth that do not extend to the base of the gear.
*The intermediate shaft has one mark on the cast 3rd gear oriented towards the 2nd gear side on all teeth. The cast 4th gear has no markings.
*Center differential case gear has no markings on all gear teeth. It also has a lower pinion gear oiling washer (brass) that has two retainer wings on the outside of the washer to hold it into the case.

The mid-1991-early 1992 differences that are obvious are:
*Large diameter 5th/Reverse synchros and hub/slider assembly.
*5th gear cover with narrow outer corner edging by 5th/Rev hub/slider assembly w/ part number "MD741185" stamped inside the casting.
*Narrow 5th cover oil guide.
*1x black plastic oil guide.
*3rd gear on the input shaft has 3 markings on the gear teeth.
*4th gear on the input shaft has 3 markings on the gear teeth.
*2nd gear is a single synchro gear with full length dog engagement teeth.
*1st gear has a thicker backside and has no number stamped on its backside.
*Center differential case gear has one mark on all gear teeth. The lower pinion gear oiling washer (brass) has one relief tab to hold it into place located on the inside of the oiling washer.

The late 1992-1999 differences that are obvious are:
*3-hole 3rd/4th shift fork
*Large diameter 3rd and 4th gear synchros
*Large diameter 3rd/4th hub and slider with wide shift fork groove
*1994-1999 came with several variations of double synchro 2nd gears.


Hope this helps!

 

[doesitonall4rs]

Damn! all that information was spot on! Thank you very much! A lot of little differences that I did not notice at a quick glance, because I was thinking the inner diameters of the gears were going to be different.

Do you think if I swapped the endcase cover and shift fork I could use the 5th gear/hub/slider/synchro assembly from my early 91 in my late 91 Trans?