NP435 to A833 swap

[Blue67]

First post. Truck is 67 D100, 318 poly, 3.22 rear, NP435 with hydraulic clutch. Second gear is way too high causing starts from granny in most places. I would like to keep the hyd clutch and bell housing but change to A833 and eventually perhaps a 360. Thus preventing fabricating new mechanical clutch linkage. I have searched many places to find info about these swaps. Some places say very hard to impossible to do. Other places say bell housing bolt patterns the same on both ends. Anyone know for sure any info about this or suggested searches.

thanks

[Hobcobble]

Welcome to the site . I believe that
there are at least a couple of guys here that can
you out on your tranny questions. If you do plan
on putting in a 360, you'll need the correct flywheel
for the engine as it is externally balanced.
By the way... you wouldn't happen to know a guy by
the name of Hayes Otoupalik from Missoula would you?
John

[Blue67]

Thanks John
First thought is to change tranny then think about small block swap later. Just thought it might be easier to keep the bell housing and mounts. Would be perfect of A833 would bolt to BH even if machine work was needed for trans input bearing and even a change of input shaft or pressure plate to match length/splines.
Way too much I don't know.
Truck sat for about 10 years before I got it last month. Back on the road now though. A work in progress. Mother Mopar did build some tough trucks.
Hayes name doesn't sound familiar.

[Jeffc]

I would have to question why your doing the swap in the frist place.
If your gears in the rear end are too tall> swap them
with a lower set.......
2nd gear starts with 3.55 gears are not a problem
with 31" tires for my 66 D100 318 4sp unless I have
a real load.
If your having to use granny to start out all the
time you got to be running a 3.32 or high gear set
(as I see above). The 3.23 is a great set if all your doing is highway driving and not pulling loads, but the 3.55 set works the best all the way around. I can run at just under 3K rpm @ 65 to 70mph with the 3.55 and around town 2nd gear starts are not a problem. Much easier swap and less money/time than what your talking about.

[Blue67]

Thanks Jeff. 28 inch tires. Dodge shop manual shows two NP435’s available as options for 67. One has granny of 6.68-1; 2nd gear 3.34-1. The other 4.56-1 and 2.28-1. Not sure how to tell which one I have or even if someone changed it out over the years. From the way it drives I think I have 2.28-1 and with 3.22 rear gears it is pretty high geared from a stop. The 833 swap would allow a first gear of 3.09 for better in town driving and still allow the sustained 80 MPH highway runs that are not unusual in Montana. Truck is not used to haul or tow but is my daily driver. I just like the idea of the easy shifting, smooth, strong 833, If it is too hard/expensive to do I could always find a 435 with the 3.34 2nd gear.

[Jeffc]

I got you, if you can find a good 833 go for it,
but you will need to change to a rear mount for the
trans (even if it will bolt to the hydro bell, I can't say one way or the other, never done that swap)
they were never set up to hang off the bell housing
like your 435. Most 833's at this point in time
are wornout, broken and/or need of rebuild anyway, which is why there up of sale.
Just my $.02 there....
If it were me I would keep what you got and get the
2nd gear changed to what you want, bet it would be a
lot cheaper/easyer in the long run. Make a few calls.....

One other thing, there are 2 types of 833's (3 if you include the alum OD type) the early ones used the ball and trunion and the late will be a slip joint.

[Blue67]

Good input Jeff. Thanks. That’s probably the cheapest and easiest way to go. Most dependable too maybe. For info. I just came back from a long drive in the Swan Mountains. Checked odometer against marked highway miles. Not the most accurate way to check but for each 10 miles traveled by the odometer we actually traveled 12 highway miles according to the mile markers. Makes me wonder what tires and rims it had when Dodge sold it.

[Jeffc]

What does your door tag say it had for rear gears?
bet it didn't come with a 3.23 rear end, that would
make the differance....

Took my 68 to the track the other day, frist trip with the tack hooked up, was trunning 2K @ 60mph on the
freeway???? What the heck is this I asked. Turns out the tag that said 3.23 on the pumkin was not right, pulled the 3rd out and guess what? 2.91's
great for the freeway but suck (big time)around town, got a 3.55 surgrip living in there now
Even had a early 657 8.75 case in there, most folks have never even hear of that case....

[Blue67]

Door tag says 3.2 Tag on pumpkin bolt says 3.22
Doesn’t mean that is what is in there now but since both are the same it does seem likely to me. Had narrow 16 inch rims on it when I bought it.
With the 20% difference between traveled and shown on the odometer I do believe something has been changed out somewhere along the line. Maybe just tires.
Anyone know a way to ID gear ratios in trans from an outside the trans number?

[Jeffc]

It's not perfect, but jack up your rear axle, both wheels, put a mark on the tire and one side of your yoke
and count the rev's of the yoke when turning the tire
once. If your 3.22 (round 3 and 1/4 turns) rev's of the yoke per tire turn,
you got your number, less than 3 your in the 2's.
(if I recall right....).

If you happen to have a sure grip unit, both tires will turn the same way, open rear will turn opposite (one front one back).

If your 15" rims now with smaller tires that would be
the differance.

[Blue67]

Thanks. I'll do that.
Are there any ID numbers on the 435 to show what gear ratios are in the tranny? Or an easy way to find out without pulling the tranny?

[Jeffc]

Not that I know of, maybe someone else has imput on that....just guessing, but you could do the same thing
with engine turns? how many engine turns to trany yoke??? never thought about it before...

[Blue67]

Appreciate all your help. Maybe pull the plugs and turn crank with socket. Wonder if I can talk the wife into climbing under and counting the trans yoke turns.