I need help with B2 transmission identification!

[SSSnakeCharmer]

I'm looking to buy a Bronco II and I only want one that has the M5OD already in it from the factory. I'm searching craigslist for B2s and most are a couple hours away so there's no way I can just look under it to see if there's a pan or not. Is there a way to identify a B2 that came stock with the M5OD? Can you tell by the VIN? I read somewhere that M5OD equipped B2s are M code... So does M code refer to the VIN or some other number on the door sticker? Any help would be much appreciated!

 

[adsm08]

Yes, that should be the VIN code. But M5OD Bronco IIs would be extremely rare, and more than likely 2wd. And BIIs aren't that common in general anymore.

If it were me, and one came up that was otherwise perfect I would grab it and swap the trans. It will get you what you want faster.

 

[SSSnakeCharmer]

Ok I'll keep that in mind. Do you know by chance what digit in the vin the m would be?

 

[RonD]

Good read here: http://www.broncoiicorral.com/library/facts.shtml
Look at the bottom and read "strange facts"

The FM146(code D) and M5OD-R1(code M) were used from '88 to '90 but as adsm said would be rare to find M5OD in a 4x4 model I would say 0 chance
But a 1990 model would be best bet to find one, and 2WD of course as per "strange facts".

The trans code is not in the VIN as far as I know, it is on the drivers door sticker.

VIN has engine code and 2WD or 4WD code but manual or automatic, or trans ID is not in there.

VIN decoder here: http://www.therangerstation.com/tech_library/VIN_Codes.html

 

[adsm08]

I don't have a VIN decoder for older ones on me, but I compared the VIN codes for Auto trans to the VIN on my Red 87 (because that's the paper work I have with me right now) and the A4LD code letter is in the VIN, next to the engine code.

 

[SSSnakeCharmer]

So If I bought a 2wd B2 that had the M5OD would it be possible to swap the dummy T case out for a 4x4 T case?

 

[RonD]

M5OD wouldn't have the dummy transfer case

 

[SSSnakeCharmer]

I'm a bit confused. I thought you said they didn't make any B2s that were 4x4 and had the M5OD?

 

[RonD]

2WD B2s had a dummy transfer case with FM145 or 46 transmission, it just had the output shaft gears, no 4x4 parts inside.
So during assembly no changes needed to be made to trans or supports or drive shaft.
just no front axle or drive shaft and no guts in transfer case.
Also the weight distribution would be about the same, there were issues with Jeeps and B2s(I would image) being unstable during quick steering maneuvers during this time.
But I really don't know why they did the dummy transfer case?

My guess are the ones without dummy transfer cases were M5OD which needed an adapter shaft for use in B2, per above link.

If you got a 2WD with M5OD you would need front axle/drive line, transfer case with M5OD transfer case housing and shaft, and the electrics unless you could find a manual transfer case.

IMO, you would be better off getting a 4x4 B2 and swapping out the trans for an M5OD if that's what you want.
'90 and up 4.0l ranger 4x4s would have M5OD trans that would bolt up to 2.9l engine

 

[adsm08]

^That^

While not totally unheard of the 2.9L M5OD 4x4 is an almost non-existent part. They were made, but they accounted for something like <1% of total production of that transmission. It's in the same category of the 4x4 diesel Ranger.

Most of the existing 2.9 4x4 M5OD units are like mine, they were converted from 2wds.

I've driven the 2.9 with a 4.0 trans behind it, and a 2.9 trans behind it, despite the differences in gearing you really don't notice it much. And I can honestly say that as I have driven both setups in the same vehicle.

 

[SSSnakeCharmer]

Most of the existing 2.9 4x4 M5OD units are like mine, they were converted from 2wds.

So how and what all do you need to do the conversion?

 

[adsm08]

You need an output shaft and an extension housing, then you take your 2wd trans completely apart, move the gears over to the 4x4 output shaft, and put it all back together.

 

[SSSnakeCharmer]

Sounds complicated lol. Maybe I'll just give up on the idea of finding a 4x4 M5OD with the D35... I didn't realize it would be such a unicorn hunt. There's an 89 for sale in my area that was towed behind a motor home half it's life. It has 148k on it, completely stock, 5 speed and has a straight body. $1750. Good deal?

 

[4x4junkie]

Agreed. get whatever looks clean and well-taken-care-of. Worry about the M5OD and the D35 afterward. Both are easy dirt-simple swaps.

My BII was an early-production 1990 model, which came with a D28, BW1350, and the FM146. It was in good shape though so I went ahead and bought it. I immediately swapped out the D28 for a 35, however I got a good 20K or so out of the FM146 before the output bearing started to make enough noise to be concerning (purposely overfilling these transmissions by a half-quart or so seems to help them last better). Swapping to a M5OD however was just a matter of dropping the FM146 and stuffing the M5OD in. Except for a minor issue with the interior trim for the shifter (mounts further forward, exposing the edge of the carpet), it was all bolt-in.

FWIW, my M5OD is one of the rare factory 2.9L 4x4 ones. It came from a 1990 Supercab Ranger. I've always had the impression this is the one & only year the 2.9L 4x4 M5OD was ever used. I've heard people say 4x4 M5ODs were used in some '90 BIIs also, but I've never actually confirmed it (seems most BIIs built after 11-'89 had the D35 & BW1354 with a FM146).
The 4.0L 4x4 M5OD is exactly the same trans except for the slight difference in gear ratios adsm mentioned. 4.0L ones are quite ubiquitous.

 

[SSSnakeCharmer]

Ok well I'm looking at 2 different BIIs to buy right now. A clean 89 with 140k that was towed behind a motor home for half it's life.. It has the 2.9 fm146 mt D28 bw1350 manual 4x4 with manual lockers and has the limited slip 3:73 7.5 rear end. The other one I'm looking at is a unicorn if what everyone says about 4x4 M5OD BIIs is true... It's a 90 manufactured 2/90 code M so factory installed M5OD has D35, BW1354 push button 4x4 with auto lockers and has the 3:73 7.5 open diff rear end. The 89 is $1750 and the 90 is $3000. Both are minty but the 90 is nicer...