I want to swap out with my 2.5 l MazdaB series motor with my 4.0 Ford V6

Jonny Paine

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Make
Ford
Model
Ranger
Year
99
Miles
298000
Engine
At 2.5 4 cylinder engine and a 4.0 6 cylinder engine
I was wondering if anyone has done this and if it bolts up properly
 

billr

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I don't know the answer, but you are wise to be wary. Neither Ford or Mazda seem too keen on keeping things standardized/interchangeable. I ran into a Ford bell-housing that had both 10mm and 3/8" threads. And the fastener heads were 12mm and 1/2", so they looked pretty much the same. Luckily (or skillfully) I caught the different before ruining threads in the bell-housing...
 

nickb2

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Oh boy, where do I start saying this is going to be a doozy.

So before I start sounding condescending, I am going to ask a few questions first.



Do you have a 4.0l engine wiring harness, 2nd, do you have a 4.0l PCM/TCM/PDC etc? 3rd, do you have the front end suspension for a 4.0l swap, cuz that engine slash powertrain is quite heavier than the 2.5l, so coil springs etc are different, not to mention what Billr said about bolt patterns and such, the 4.0l is NOT a mazda design.
 

nickb2

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The 4.0l swap to 2.5l will NOT, repeat, will NOT bolt to tranny etc, you may even need a cluster.

Basically, to make this doable, you need a doner truck. That, or a lot of impatience and cash.

Swapping a 4.0l to a 5.0l would be way more feasible, but a 2.5l to a 4.0l is nearly impossible without a whole doner truck.
 

nickb2

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Now I am going to sound condescending, you could probably fit a 302 easier in there with less head ache, just chuck anything 2.5l related. If you peruse the net, you will find alot of threads like this, they all end up pretty much the same, not doable.

But I am not one of those guys who says it cant be done, cuz anything is possible with a bottomless wallet.

So basically, do you have a endless wallet? if so, sure, it can be done.
 

nickb2

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Wow, its raining cats and dogs and close to 1celcius, so yeah, going out and having fun is not in the agenda.

so I went through a few threads on line about this, I found NONE that were successful with out a doner truck.

 

nickb2

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Jonny Paine

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The 4.0l swap to 2.5l will NOT, repeat, will NOT bolt to tranny etc, you may even need a cluster.

Basically, to make this doable, you need a doner truck. That, or a lot of impatience and cash.

Swapping a 4.0l to a 5.0l would be way more feasible, but a 2.5l to a 4.0l is nearly impossible without a whole doner truck.
So here's the deal, I have a 99 Ford ranger with the V6 4.0 and a automatic transmission. It's not in the greatest of shape and I really really want the 5 speed manual. I also have a 98 Mazda B series 2500 with a 5-speed manual and the 2.5 l piece of shit with 4 cylinders and 8 spark plugs. I either want to take my 4.0 and drop it in the Mazda. Or I want to take the high-speed manual out of the Mazda and put it in my Ford
 

billr

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As said above, any kind of swap is "possible". Some of things I would be wary of are:

1) Bell-housing pattern and depth. Most likely you will have to use the Ford flywheel and pressure-plate. You may end up using a Mazda friction disc because of the splines needed. Does the Mazda trans need a pilot bearing in the crank? The lineal relations of the trans shaft, disc location, and throw-out bearing all need to be checked. The throw-out bearing and fork must fit over the snout of the trans; those may need to be Ford, Mazda, or something other to make this all come together. Custom fab or machining of some parts may make this quicker/easier than chasing down standard parts from other applications that will work; but probably will be more expensive. The Ford starter motor probably mounts on the bell-housing, is that going to work OK with the Mazda 5-speed bell-housing? Does the Ford bell-housing for a manual trans separate from the (Ford) trans, so it could be adapted to the Mazda 5-speed?

2) Check how the steering and suspension parts clear the oil pans. If the sump on one engine is at the opposite end from the other, then some real trickery may be needed. Sometimes a "tunnel" (tube welded in) is needed in the pan for steering rods to pass through!

3) Motor mounts. If they are different on the two truck frames, then some custom fab/welding will probably be necessary.

4) Width of the V-6 on top. Will the heads, and accessories like alternator, PS, A/C, etc clear the shock towers, frame, brake-booster, wiper motor, etc? How about the firewall, will the back of the V-6 clear that if the trans is left in the original place in the Mazda? You really would want to leave the trans in the same place, to avoid having to change shift linkage and drive-shaft length.

5) Or, if the 5-speed goes into the Ford, you probably need to fuss with the drive-shaft (length and front yoke) and provide all the clutch and shift operating stuff.

6) Is there room to fit a radiator big enough to cool the Ford into the Mazda? Custom radiators are readily available, but not cheap.

7) I assume you have no emissions testing/requirements, and are free to do (and pay) for whatever exhaust mods are needed. I'll also assume a clutch and flywheel is readily available for that Ford engine. Even if that is the case, be sure the crank is configured to take a pilot bearing (if needed).

8) Check clearance from the top of engine to hood, once you figure out what the engine mounts need to be.

9) Electrically it would be much easier to put the 5-speed in the Ford, but mechanically (clutch and shift linkage) maybe the other way around. Which truck do you like better over-all, and which is in better condition?
 
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