Replacing the old 300

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Apr 29, 2002 | 11:35 AM

tmcalavy

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Replacing the old 300

May 1, 2002 | 04:57 PM

72400

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Replacing the old 300

I have a 73 merc that I bought as a "good deal" turns out it had some hidden rust. I was wondering if it would be possible to swap the 400 2v from the merc to replace my tired 300.

1972 f-350 dump
4 spd man.

What would need to be changed? My main concern is if the mounts and the tranny will bolt up fine.

May 1, 2002 | 05:17 PM

thatdude

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From: McPherson, Ks

Replacing the old 300

72400, the trans from the 300 wont bolt up,use the one out of the merc, I went to a one piece drive shaft (had to get it cut, $50),
I had to get an aftermarket floor shifter.

This is how I did it but there is more than one way to skin a cat.

May 1, 2002 | 07:10 PM

62stepside

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Joined: Mar 2001

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From: Suwanee, GA

Replacing the old 300

Correct me if I'm wrong, but didn't they stop making mercury trucks in '67 or '69?

Tyson

May 1, 2002 | 09:45 PM

thatdude

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From: McPherson, Ks

Replacing the old 300

I am assuming the merc is a car.

May 2, 2002 | 11:20 AM

72400

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Replacing the old 300

the motor is out of a merc meteor montcalm. The thing is the car is an auto, and we really need the gears for hauling heavey loads. Would the auto stand up to the task or is there a manual tranny that will bolt up to the 400 with "truck gears". If there is what vehicle/engine does it come from?

Thanks guys, I'm new to this.
Steve

May 3, 2002 | 09:43 PM

thatdude

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From: McPherson, Ks

Replacing the old 300

C6 tranny's are very stout, I would be suprised if it failed under hard use, (a trans fluid cooler never hurts).

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May 4, 2002 | 09:21 AM

evans

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Replacing the old 300

Ford put manual trannys behind 351M's in the later 70's. This bellhousing will bolt to your 400. Your 4-spd should bolt to the bellhousing. I don't know what you will get into with the flywheel. The 351M flywheel should bolt to the 400 but I'm not sure if it would have the correct balance weight. I'm pretty sure it's the same, I don't know for sure. Don't forget the pilot bushing for the 400. You will also need the frame perches and motor mounts from the later 70's truck that had a 351M in it. Car motor mounts are different. As for the C-6, they are great trannys and very heavy duty but if there are many hills wher you are I would stick with the 4-spd in a 1 ton dump.

MIke