Okay so has anyone ever swapped an overdrive into a 1991-back? Whats required to make it work? Yes I know its a 3.07 ratio but this truck is a highway cruiser that occasionally hauls parts and nothing more. I am just curious as to what it would take.

Thanks
RAM

 

Being a D, it should be fairly straight forward unless you expect OD to operate as a 91.5 up. You will have to shorten the drive shaft, you may have to reposition the cross member. But either of those are fairly simple. As for activation, a simple on/off switch will do. Just remember to turn it off when you stop. You can go one step further and do a 47RH swap. A little more work, but doable.

 

The bracket for the A-518 mount that goes between it and the crossmember is different IIRC too.

 

Oli you are the man! Since this is a low budget parts chaser and not a tow rig I think I will keep an eye out for a spare 3spd. The only reason I was asking is the cooler popped last week and my dad revved the crap out of it to get it up to his shop. I got home from work and then found all of the trans oil was all over the place. I found a replacement cooler and bought a Mag double deep trans pan from Genos. It took 12qrts to fill it!!! It runs really well now. Its amazing how hard the non I/C truck stuff is to get around me. A lot more I/C trucks. Thank you for Shari your knowledge my friend

 

Glad to help out, there RAM.
They did make A LOT more of the '91.5-'93 trucks than the '89-'91.0 trucks, so it is not a shock they are harder to come by 30 ish year later.

 

I know I have a few A-518 and Getrag set ups in 2wd, but I am pretty sure the only Cummins 727 options I have are all 4x4.

I do have that the old 2wd 318/360 gasser 727 left from my '78 Ramcharger 12v / 47RH build, but that will not be much help.