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351m 400 ID

I have read on several sites that the only way to tell the differance in these to engines is the either check the casting number on the crank or put something in the spark plug hole and check the stroke. A person that I trust on fords told me that an easy way to tell is to look at the oil dip stick. If it comes from the oil pan on the drivers side, it is a 351m. If it comes from the timing chain cover on the right front it is a 400.
I figure that with so many people that know their engines on this site, a look at your engine might verify if that is a good ID or not. Or maybe someone knows why the dip stick is in differant locations on these engines.
 

1985 Ford F-150

Country Boys Can Survive
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Tooele, Utah
My guess as to the dipstick bein differnt is a car motor and a truck motor or a 2wd and 4wd I know on FEs its like that but just a guess for these ones. Id just pull a plug and check the stroke with a dowel.
 

DNFXDLI

The Token Canadian
Staff member
Looking at the shop manual, it appears the dipstick is in the same location for both engine sizes.
 
I guess what I'm looking for is to have people that know their engine size to post the location of their dip sticks so that maybe we can find if this is true or if it is just a 2wd vs 4wd thing.
 

DNFXDLI

The Token Canadian
Staff member
The shop manual makes no differentiation whether it is 2WD, 4WD or engine size...this is from a Ford shop manual.
 
The dipstick on my 351M is on the passenger side. What you read earlier is correct, the only way to determine whether you have a 351M or 400 is to measure the stroke or check the crank casting number.
 

DNFXDLI

The Token Canadian
Staff member
It does not show the dipstick coming from any other place than the oil pan at the sides. It appears that the dipstick can be located on either the passenger or drivers side depending on which way the oil pan is mounted (4 x 2 or 4 x 4). I can't see any pictures showing the dipstick coming out of the front anywhere in my manual.
Maybe Dennis or someone has more info.
 
It does not show the dipstick coming from any other place than the oil pan at the sides. It appears that the dipstick can be located on either the passenger or drivers side depending on which way the oil pan is mounted (4 x 2 or 4 x 4). I can't see any pictures showing the dipstick coming out of the front anywhere in my manual.
Maybe Dennis or someone has more info.

Mine comes out of the right side of the timing cover and not out of the pan. 78 F150 4X4 C6 auto. Casting number on the block is a 77 casting for a 351M or 400. I have looked in the local junk yard and I have seen them in both places.
 

DNFXDLI

The Token Canadian
Staff member
I have no idea then...hopefully someone else can chime in.
 

LEB Ben

Arrogant A-hole At-Large
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I have 2 400's currently and they along with any other truck I've had, had the dipstick come out on the driver's side. If the dip stick comes out the front, it's a car engine...just read this in my Tom Monroe book.
 

LEB Ben

Arrogant A-hole At-Large
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I still say a front dip stick is a car engine that was swapped into a truck. A couple books I have read say this, Bubba's M Block says this and I can see no reference to a front dip stick in my TRUCK manuals.
 

gsxr1238

Be fast.....or be last.
My '78 F250 with the 400 has the dipstick and tube on the passenger side into the timing case as well.This was not a transplant as it is original.
 

LEB Ben

Arrogant A-hole At-Large
34,919
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outside your house
My '78 F250 with the 400 has the dipstick and tube on the passenger side into the timing case as well.This was not a transplant as it is original.


Did you buy the truck new off the lot? Cuz a lot can happen in 32 years. If I need to scan my references in, I'd be more than happy to.


Edit...not trying to be argumentative, but the literature I have all says the same thing. But that doesn't mean Ford didn't mix and match left over parts or grab what they had to finish a job, they seemed to be notorious for that.
 
Last edited:

gsxr1238

Be fast.....or be last.
Yes,the truck was new off the lot.I am the one and only owner of it.I am not trying to argue either.Mine looks just like the #13 post on this thread.I wonder if the dipstick location has to do with the sump location?You guys have front or rear sumps on your 4x's?
 

DNFXDLI

The Token Canadian
Staff member
Mine is a rear sump and the dipstick is on the drivers side.
 

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