Hi guys, I recently swapped my A518 for a 47rh. A friend of mine is considering swapping his 727 in his 89 for my old A518. If we swap the transmissions, will I need to get a new crossmember or can we use the existing one in a different location? I already know the driveshafts will need to be changed but am I overlooking anything else parts wise? Both trucks are 4x4. Thanks

 

you should be able to use the same crossmember. The only other thing i can think of is the wiring for the OD but that is very simple.

 

You can use the same crossmember the mount for the 727 is in the same place as the 518.

 

Will the transfer case from the 727 work for the a518? I'm looking at a 90 w250 with a blown tranny and looking to put in an OD. Also will 3.07 gears and 285/75r16 tires get along with the a518 for normal driving and light towing ( less than 5k)

 

yes the transfer case will work fine. i will let someone else chime in about the gearing but i do know that guys with the 3.07 gears and OD love driving it on the highway.

 

DO it you will love it. I just took a 221 mile trip average speed was 75-80mph and I only used a little over a 1/4 tank of fuel. The gearing is the same the only difference is there is a extra taller gear to help out with things and make the engine so much happier at highway speed. As far as towing it is the same as any other overdrive, don't tow up hill or when your lugging in od, I would say flats and down hill would be fine but you just need to be cautious not to burn up the od clutches. As far as the transfercase it will work the only thing you need to do is take the locating pin out of the flange on the transfercase or drill into the trans, I took mine out.