1st gen Cummins swap trans question

[ChicagoDII]

I bought an entire '90 Ram 250 from a local yard, and am putting the 6bt and D70 from the ram, plus a chevy D60 into a chop top and caged Range Rover. Yes, firewall cutting is needed, but will it fit is not my question.

I dont know shit about the transmissions made for this engine. I am looking for something thats a 4spd auto w/ overdrive. The truck came with a 3spd 2wd auto i was told by the yard guy. No idea what trans it is, it says CAV1 on the housing. I was told by a friend the best option would be a 47rh out of a 95 ram with a cummins, and just get the bellhousing adapter to mate it to my motor. I have also heard that an A518 is ok, but can you get that with a lockup converter? Sorry for all of the stupid questions, but I do need a bit of advise. Thanks.

[mondtster]

First off, you have an a727 3 speed automatic tranny.

Second, your two easiest options would either be a 47rh (a618) tranny out of a '94 or '95 Dodge with a CTD or a 46rh (a518) out of a '92 or '93 Dodge with a CTD (I can't remember if they had them in '91 or not). The 47rh would have OD and a lockup converter while the 46rh would just have OD. I don't think the bellhousing adapter changed between the a727 3 speed automatic trucks and the 4 speed automatic trucks, but I'm not real familiar with the earlier 1st generation Cummins Dodges either.

[MMiller]

Originally Posted by mondtster

First off, you have an a727 3 speed automatic tranny.

Second, your two easiest options would either be a 47rh (a618) tranny out of a '94 or '95 Dodge with a CTD or a 46rh (a518) out of a '92 or '93 Dodge with a CTD (I can't remember if they had them in '91 or not). The 47rh would have OD and a lockup converter while the 46rh would just have OD. I don't think the bellhousing adapter changed between the a727 3 speed automatic trucks and the 4 speed automatic trucks, but I'm not real familiar with the earlier 1st generation Cummins Dodges either.

This is correct. 89-91 came with the 3spd non lockup 727. 91.5 to 93 were non lockup, OD transmissions called the 518, the same as the 727 with and OD unit on the back. 94 to about early 98 they ran the 47rh which is an lockup convertors, OD transmission, that requires no electronics to make it work. There are TONS of aftermarket parts for this trans. 98.5 and up have 47re, which are electronic controlled transmission. You will need a computer, module, controller, to make this work right. My first choice would be the 47rh, as it has lockup convertor, and doesn't need any electronics to work. A 518 will work fine though, they work good even towing in the first gen dodges, they just make more heat from the convertor when towing. Be prepared to have a TPS sensor on the injection pump.

And just so you know, the axle that came from that truck will likely have a 3.07 gear ratio, is called a dana 71, and you will have to come up with some ring gear spacer to get any other ratio to fit into that housing. Don't trash the 3.07 parts, as they are made from un-obtanium and many first genners are looking for those parts. You could find someone that wants to trade a 410/355 dana 70 for your 307 geared dana 71.

Michael