Tranny Change To 4 Speed Or Overdrive

[Dave]

I have a 57 D200, 3/4 ton, with a flathead 6 and 3 speed on the column. 2nd gear is giving some trouble, synchros need to be replaced, but I'm doing ok by revving up when down shifting. Works good most of the time, thanks to this forum for recommending that and describing step by step how to do it. I can pull the gear box and replace the synchro, but I'd like to look into putting in a 4 speed, if the final drive is lower. Are the 4 speed boxes lower or are they the same as the 3's? I'd like to get the rpm's down when going 50 on the highway, is overdrive an option? Thanks for the help...Dave

[Young Ed]

The OEM 4spd swap by itself will not gain you anything. 4th gear is the same as 3rd in the 3spd.

[Plymouthy Adams]

first gear of the 4 speed if usually referred to as granny low...the typical driver in a unloaded truck will use 2-4 and as Ed states...4th is still just 1.1

[Dave]

Yep, that's what I figured, any over drives out there? If they are not available then I will look at the rebuild on the 3 speed or put a top loaded 4 speed if I find one.

[Scruffy49]

Get the parts to run an S10/Camaro or Dakota/150/1500 5 speed. Will save you a lot of aggravation in the end. I seem to recall your truck has the jumbo wheel bolt pattern like a one ton, which pretty much negates a simple rear axle conversion to get the same effect.

[Plymouthy Adams]

next manual OD set up came in much later in the miser series truck/vans in the 833 case I think..

[41/53dodges]

an S10 T5 transmission is the generally accepted best transplant, there is even a kit available to mount it and it requires little modification. only problem is the lack of an e-brake!

[Dave]

Cool! I should be able to find an S10 tranny easy enough, look into a kit. But, man, what do I do about an e brake? I don't think the existing rear brakes could be modified to serve as e brakes. Any ideas on this line of thought?

[Scruffy49]

Tire chock. Or better yet a linked together pair of them. You'll already be parking in gear, the chock is just added insurance. Most truck stops and big rig dealerships stock them. I even use them with my 5spd baby Ranger, the parking brakes are a farce and the transmission is more like a "transmissing" if the bed is downslope of the hood.

[pflaming]

Should you put in a 97 Cherokee rear axle, easy to do, then you could easily connect to that e-brake assembly. In fact, when the axle is picked, pick the e-brake line and connection box and you have it all.

[Dave]

Well, all those are possible. But I think a rebuild this winter on the 3 speed is in order. Maybe some day a new rear axle, but not now. The wheel chocks are a great option, I have a good rubber one already. Don't forget turning the wheels into the curb.

On another post I wrote about the steering at 50 mph, new tires up front have made a ton of difference. I can feel comfortable

Now at 55 mph, that's all I need. Dave

[55 Fargo]

Yes you have some options, with either going with the S10 transplant, you could either use wheel chocks or swap out the diff, for a Mopar 8 1/4 or Mopar 8 3/4 that will swap.

On my truck 1955 Fargo 251 4 spd, have a 3.23 Mopar  8 1/4 inch diff. Today just scooted down my gravel road at 55 mph, tach was showing 2300 rpm, at 60 it is around 2500, very comfortable with this. If I went with taller tires, this could be even better. With 4.11 rear gears, my engine would be spinning at 3200 rpm at 60 mph, not my idea of fun, especially with an old engine with some miles on her......