55.2-59 1958 Apache Help

[bowt1ed]

It depends a lot on your anticipated driving - occasional, daily, highway? TH350 is a reputable, sturdy transmission, but if you are planning on driving some highway miles, look into a 4th gear and overdrive to drive the RPM's down (i.e. 700R4). Of course, there are other things to consider - what diff ratio do you have, keeping the 350, etc.?

Cheers, Jim

[bobinbc]

Originally Posted by RostaRob

I've decide to make my first upgrade and swap the manual transmission for a automatic. Can anyone recommend a decent swap? I think I've read that the 7004R would be a good match. I have a 350 engine and am looking for some help. Thanks. Rob

One thing to consider will be how is your engine mounted? stock mounts go on the front of the block but a 350 can also be side mounted. You will want side mounts and a new crossmember to mount the transmission. Use the search feature and look up 700r4, automatic transmission, steering column etc. This is a great resource but if you haven't done this kind of work before you need to do a pile 'o reading to get some ideas...welcome to the madness!

[RostaRob]

Thanks Jim and Bob. Jim-I plan on just driving it occasionally as nice weather permits and probably on the freeways also. I do plan on keeping the 350. Forgive my ignorance but how do I know what differential ratio I have on my current rear end?
Bob-Are you saying I have to remount my engine differently if I go with the 700R4 automatic?

[Black_Sheep]

If you are starting from scratch, do a 700R4. Having an overdrive will make the truck a lot more enjoyable to drive.

[nail pounder]

https://www.ringpinion.com/calculators/Calc_RPM.aspx


I would recommend the 700r4 as well. I tried to attach a link, but if it didn't work just Google a "differential, mph, rpm calculator" you can input your rear end, tire size and mph and see what rpm you are at with OD or just a 1:1 ratio trans. I'm running a 350/700r4 w/ stock 3.90 rear end and 235/75/15 (28.5" dia) and I can cruise 75 all day at 2500rpm. Way better than the 3 on the tree it had! As others said, do some reading, some years are better than others. After I swapped in this motor/trans I took my driveshaft to be shortened and I was back on the road.

[bobinbc]

If you have the stock front mounts you can leave them and hang an auto on the engine with a trans mount/crossmember, but it is asking for trouble if you drive it hard.
If the rear is stock it will have low gears. 700r4 is a great mod.

[RostaRob]

Thanks for all of your input but I decided to go with and purchased yesterday a turbo 350 automatic trans. Since I will be needing a shifter (floor mounted) can anyone recommend a good one for me? Sorry if I dint seem like I know to much about this...it's is my first classic truck. Rob

[RostaRob]

Finally got my truck back from paint.

[nail pounder]

Originally Posted by RostaRob

Finally got my truck back from paint. Attachment 1901799

Looks great! I like the stance, what route did you end up going?

[RostaRob]

I'm not sure what you mean by that but I put in a Heidts front end and C notched the frame. Turbo350 trans. Drives great!

[nail pounder]

Originally Posted by RostaRob

I'm not sure what you mean by that but I put in a Heidts front end and C notched the frame. Turbo350 trans. Drives great!

Yes, thats what I was asking. Your first post in this thread you were asking about different options to lower it. Looks nice. I'm surprised you went with a turbo 350, did you swap out the rear end or just stay off the freeways?

[RostaRob]

I don't really plan on driving it that much on the highway, plus I got a good deal on the 350 turbo. Yes I did swap out the rear end from at 67 Camaro, 3.08. Runs down the road...and highways just great. I also had to put wheel spacers on it to properly fill the wheel well.