swap in 318/A518(46RH)?

[lylebailey1]

Been looking without much luck to see if this can work.
My '54 had a transplanted chevy 327/4spd which the PO kept, leaving me with decisions to make.
I have access to an LA 318 and an LA 360, both automatic. Found a '90 W150 with an A518 auto o/d trans parts truck.
Want to go automatic (so my father in law can also drive it) but it seems there is not enough space.
The Chevy 4 speed was 20" long and I believe the A518 is approx. 31" leaving no room to mate to the divorced transfer case.
Really like the idea of having a 0.69 o/d - this is not a winch truck, nor is it being off roaded/crawling. Will be a year round driver with a snowplow.
Planning on keeping at least 900 x 16s or taller on her as well. ANY insight etc would be greatly appreciated! Thanks in advance

[W_A_Watson_II]

The 1990 V-8 with a A518 and a NP241 Transfercase will put the output yoke almost exactly in the same location fore/aft as the stock setup, but will be a centered output rather than offset to the passengers side.

[Kaegi]

there are short shaft 727 that will fit but then no OD

[lylebailey1]

I'm confused about the term 'centered output'. I haven't been under the parts truck to see the transfer case orientation.
Am I to understand that the np241 won't connect to the original M37 front axle?

O/D is a high priority in making this a road buggy.

[W_A_Watson_II]

A passenger side drop NP241 will connect to the front axle OK, but the rear output is centered and the rear drive shaft will be on an angle.

[lylebailey1]

Considering that the rear driveshaft length would be similar in length, do you think the angle would be slight enough to survive normal operation?

[W_A_Watson_II]

As long as the angles cancel out it will be fine, but if it's too short you might end up with a double cardan drive shaft to make it work. I'm sending you a PM with a link to an image.

[Kaegi]

but istn a 241 chain drive? cant beat stock 200 gear drive for durability. I cant stand the feel and sound of chain drive tcases.

[just me]

I've had better durability with chain cases over gear cases in hard sustained use. They run so much cooler. And where ambient air temperature is routinely over 110, that is important. And both gearcases have the same amount of slop. The chain one is more cushioned feeling.

[Kaegi]

I've had better durability with chain cases over gear cases in hard sustained use. They run so much cooler. And where ambient air temperature is routinely over 110, that is important. And both gearcases have the same amount of slop. The chain one is more cushioned feeling.

I have seen many broken chain drive cases. I have never seen a broken gear drive case. that's over a 30 plus year period. I am sticking with gears.... in the mountainous offroad terrain out here in the west chains just don't hold up the same

[rickf]

If you go with a centered output you will have vibration due to compound angles in the u-joints. If you go that route then a CV or redesigned driveshaft similar to a M151 front shaft where the u-joints are designed out of phase to compensate for the compound angles.

[rickf]

Chain vs. gear, sort of like the which oil is better debate. I have seen quite a few 205 cases split right in half and left the bottom half with driveshaft laying on the ground. So yea, they do break too. I seriously doubt you will break either one behind a 318.

[lylebailey1]

I have found that this M37 has 4.89 gears!
If I WERE to install the A518, that would give me an approx. 3.38 in o/d.
The average annual temp in my part of Maine is 54 degrees.
Am I foolish to think 3.38 is TOO far?

[W_A_Watson_II]

If you go with a centered output you will have vibration due to compound angles in the u-joints. If you go that route then a CV or redesigned driveshaft similar to a M151 front shaft where the u-joints are designed out of phase to compensate for the compound angles.

Not True, If the engine is installed properly aligned the angled drive shaft will not introduce any vibration.

[W_A_Watson_II]

I have found that this M37 has 4.89 gears!
If I WERE to install the A518, that would give me an approx. 3.38 in o/d.
The average annual temp in my part of Maine is 54 degrees.
Am I foolish to think 3.38 is TOO far?

Michael Verst is running the A518 with a 360 and 4.89 gears and cruising the highways everywhere he takes his truck.

Me I've gor the A518 behind a 318 with 5.83 gears and 60 MPH is about 2100 RPM. and no problems.

https://www.facebook.com/myclassiccar/v ... 520669012/