Fm 146??

[lukeburris53]

I've got a 90 BII, auto that is no good. I've been looking for a while, calling all over the state for a mazda 5 speed. I got one quote for $1500 and one for $450 plus some fees or something. I can get an FM 146 for $150 probably, or definantly one for $350. All of those numbers are before clutch, pedals, etc.

I would really prefer to not throw $600 into the thing, which the chance it could just die and become even a bigger money trap.

So my question is can I get away with a FM 146 for fairly simple driving? It won't be going more than 15 miles on the road at a time, and won't be in any serious off road situations. And per say it does go out, is it possible to rebuild it reasonably? thanks..

 

[Jspafford]

The FM-146 is a piece of crap. If you were going to go through the hassle of swapping in a manual get a M5OD. They are far superior to the FM series.

 

[Mutant Pony]

My fm146 is over twenty years old, has an unknown amount of miles, Has hauled loads way beyond what it is rated for many, many times. And I have beat on it on the highway, in the woods, mud and sand. I doesn't click, whine, or shift hard. If I had the gas money I would drive it to Texas right now (Across country). If you look hard enough you can find a complete parts Ranger for a couple hundred, pull all the parts you need, throw all your scrap in it, haul it to a scrap yard and get your money back.

 

[Jspafford]

I went through the stock one in 80K, and got a replacement supposibly rebuilt. It lasted 5K, got another one, it was loud when I put it in.

Had AllanD build me a M5OD about 15K ago and it is quiet and shifts way better than the FM146 ever did, especially when cold.

 

[MAKG]

I ususally recommend against using an FM1xx unless it's already in the vehicle and working. Having been inside these transmissions, there are a number of nice design features, but ONE big F-up. The input bearing can barely handle the load under nominal circumstances. Put some common off-nominal conditions (wrong fluid, towing in 5th, shock loading, lack of maintenance, a working 4.0L, etc.), and it dies quickly.

If you already had one, I'd say use it until it dies (if it ain't broke, don't fix it). But since you don't, I'd advise strongly against getting one.

 

[rednine4]

The Fm146 usually gets a bad rap.... It is weaker, bad bearing design ect... On the flip side I beat the piss out of the one I had with an unknown amount of miles on it and it took every bit of it..... Also they have a smoother shifting mechanism than the m50d does.... not to mention they are easier to come by... at least they are around here. If you plan to use and abuse it be safe and go with the m50d. they are much stronger and reliable than the 146.....if you just drive easy and dont use 5th gear alot or if you have 3.45 gears the fm146 is a acceptable trans In my opinion.

 

[MAKG]

Differential gearing is irrelevant to the transmission. It sees peak engine torque, period.

 

[rednine4]

MAKG You simply misunderstood me... Differential gearing can be relevant to the life of the transmission. A vehicle with 3.45's is far less likely to spend as much time in 5th gear as a vehicle with 4.10's..

 

[Jspafford]

MAKG You simply misunderstood me... Differential gearing can be relevant to the life of the transmission. A vehicle with 3.45's is far less likely to spend as much time in 5th gear as a vehicle with 4.10's..

I have 3.45 gears in my Bronco II (which now has a M5OD) and I use 5th anytime I am on the freeway above 50mph. It still runs at 2500rpm at 65mph.

 

[lukeburris53]

Well it sounds like it just depends on which FM 146 I get. I just don't know if i want to throw another $300 in it.

And just to make sure I don't have something messed up: M5OD has NO drainpan on the bottom. The FM 146/145 do. And the 145, which was pre '88, is two inches shorter than the A4LD. The FM 146 is '88 on, and the same length as the A4LD. Did I pass?

 

[MAKG]

Well it sounds like it just depends on which FM 146 I get. I just don't know if i want to throw another $300 in it.

And just to make sure I don't have something messed up: M5OD has NO drainpan on the bottom. The FM 146/145 do. And the 145, which was pre '88, is two inches shorter than the A4LD. The FM 146 is '88 on, and the same length as the A4LD. Did I pass?

Pretty much. I'd add a few details, though.

1. There are 2WD M5ODs. No, you can't convert them to 4WD without critical special 4WD parts (like the mainshaft) and a lot of effort.

2. TK4s and TK5s also have drainpans. They are aluminum instead of steel, and they also aren't very good (and are all shorter than A4LDs).

3. Sticks do not interchange between transmission models. Make sure you get it. Specifically for manual transfer cases, the shift levers are also different for M5ODs than for anything else.

4. M5ODs have integral bellhousings. Get one that fits your engine.

5. Almost all transfer case flanges are the same. The only exceptions are the AWD transfer cases from 5.0L Explorers and Aerostars.

 

[lukeburris53]

By integral bellhousings, do you mean that I have to get one from a 2.9L or a 4.0L?

That $450 one I had the lead on hasn't come around like it was supposed to, so that one may be out of the question now anyway.

 

[Jspafford]

Yes, meaning the bellhousing cannot be removed, so make sure the holes will line up with the motor you have. Easiest way, get one from the same motor.