I have a 1984 c10 with 3 on the tree and a 4.1 l6 engine. Whats my automatic transmission options and whats involved in converting? I have to get a new rear end also due to mine being locked up. What the best tranny/rear end combo for fuel mileage?
you have the best combo for MPG.. why is the rear end locked up??? or is the transmission locked up .. sorry.. i have to ask because i am curious.. and rear ends are easily rebuilt ..or exchanged.. you have a LOT of options... do you have an end use for the truck.. is it going to be a daily driver.. or haul stuff or tow anything.. you could almost drop a TH350.. or TH350C in without changing much of anything.. flywheel to flex plate.. transmission oil cooler lines.. even the drive shaft and yoke should fit.. the cross member is probably in the proper place.. you could get a 700R4.. but you will need to figure out the throttle cable linkage.. as that is critical for adjustment and pull verses angle.. finding a straight six with a 700R4 is going to be hard to get the proper linkage.. you could also go the other way.. go to a 5 speed manual transmission like an NV4500.. as that has a top shifter and will mostly bolt it.. you may have to do some hydraulic clutch conversion.. what gear ratio you select depends on the tire size you are running.. for best economy you want around 1800 to 2000 rpms at 60 mph. in top gear.. it also depends on where you live.. if you drive up and down a lot of hills.. you will want to go to a slightly lower gear.. if you drive across miles and miles of flat freeways.. thats about right. hint.. if you dig deep.. there is an MY6 transmission that is a 4 speed overdrive.. that came in chevy trucks.. you need the bell housing and the shifter. and they are kinda hard to find.. they are a new process A833 that was modified to have the third gear position as direct drive and the 4th gear position going thru the cluster gear and spinning the output shaft faster.. hint.. you can use your existing 3 on the tree shift linkage.. to shift all 4 gears.. and use a morse cable.. like a PTO engagement cable to control reverse... and you get a better feature... if you pull the transmission into reverse.. you can also select one of the forward gears and this will lock the input and the output shaft.. this is like having PARK in a manual transmission.. you could also do this with a saginaw or a muncie 4 speed transmission.. just not having the overdrive.. the biggest issue is the drive shaft length and the proper transmission yoke...you will need a proper straight six flex plate and flex plate to crank bolts.. but thats fairly easy.. if you go to an automatic.. just swap the steering column completely.. it unbolts and comes out in 20 minutes or so.. when you are removing the donor column.. you have a choice of tilt or NON TILT.. depending on the year.. of the donor.. as there are a lot of years that will bolt in.. you will probably want to stick with the wiper switch on the column.. and you will need to find one with the same turn signal/wiper/cruise or no cruise control stalk as you have.. or swap yours over.. oh.. and on automatic transmission columns. there is a tiny string attached to the bottom of the shifter bowl on the right side.. if you don't disconnect it.. you will break the dashboard of the donor truck and you may need that to put a shift indicator in yours..