The truck: '90 F-150 4x2 300-6 & Mazda 5-speed. Almost 110,000 miles.

I was going to follow everyone's recommendation about servicing the
Mazda tranny and replace those leaky plugs, but I'm not sure I have
to now. Here's why: the ford dealer swears up and down that there are
no rubber shift plugs on this transmission for that year. There are 3
steel plugs, but they're forward of the shifter. The exploded diagram
he showed me of the transmission seemed to agree.

I think that might be right, because I checked the fluid level and it
was right up to the fill plug. Couldn't have been more than a
quarter-inch low, if that. I drained it, and the fluid was brown. And
I mean *BROWN*. Put next to the oil I drained the same day, you cannot
tell the difference. The only reason I think it's ATF is because it
foamed real easy. So my guess is it's the original, 110k mile, 12 year
old fluid. If it leaked at all, you'd think it would be a lot lower.

So before you tear the cab apart to replace the plugs, check the fluid
level & age first. Shifting was a lot easier, too. I don't have to jam
it into first anymore. It pops right in. It's so nice!

Now I have a question. There's an inspection port for the clutch
housing on the driver's side of the transmission, about 3 inches or so
behind where the bellhousing bolts up. The port is covered by a rubber
plug about 2" by 3". Right behind that port, and facing the back of the truck, is another port. There was no rubber plug on it, and I can see right into the tranny. Shouldn't there be another plug there? It seems like there should be.

Sorry for the long post.. I also changed a leaky oil pan gasket, and
this was the first serious repair I've ever done. I'm quite proud it
doesn't leak worse.

 

Don't know about any potentially leaky plugs. My '95 has the Mazda 5 speed and at 90,000 miles still hasn't leaked. I do recall looking at an earlier year (I think 90/91) that seemed to be leaking fromteh top of the tranny.

As for inspection ports, if I recall correctly, the rubber plugged port is on the bell housing and the other port is at the very front edge of the bell housing and is only about 1/4 to 3/8 inches wide but runs 2 or 3 inches along the edge. That on I always thought this one on the edge was not supposed to be plugged because I think it is a drain as water likely gets in the bell housing one way or another. I also assume the port with the rubber plug is where the lever would go for a traditional clutch mechanism with the slave cylinder mounted outside the bell housing.

 

My 96 doesn't seem to leak at all. Shifting in 1 and 2 is kinda rough, but not bad at all for 101k.

I've read numerous posts about getting the plugs replaced, but I don't think I need to get. Fluid level is always maintained and doesn't appear to be leaking.

NJK

 

The Mazda tranny definitely has the 3 rubber plugs as I just had mine out and had the plugs replaced. It also has the 3 steel plugs that face forward of the transmission. The rubber plugs face towards the back.

Marty

 

Marty, can you tell me exactly where they are? I can't find them on the diagram anywhere. I can't find them by feeling around on top of the transmission, either.

 

Hey Andy. Here is a link to a post here on FTE for the Mazda 5 speed.

https://www.ford-trucks.com/articles/april2002/m5od_tranny.php

I checked my Haynes manual but it doesn't show the Mazda. Maybe one of the guys on here might have it. I can tell you that the rubber plugs are behind the shifter--if you take your shifter out you can almost reach them from there. There are three of them in a row just as the three steel plugs are in a row.

Let me know if this link helps you.

Marty

 

Actually, I already read that post. It was very informative, but I still believe that some Mazda 5-speeds don't have the rubber shift plugs. The only place I can find an exploded diagram of the tranny is from the ford dealer. I have both the Chilton's and the Haynes books, and neither one has a diagram, or even a picture that would help straighten this out. The dealer was nice enough to print the diagram out, but as I said, it doesn't show the location or existence of the plugs.

I think I'll just keep an eye on the fluid. I'll probably check it everytime I check the oil and hope it doesn't spring a leak in the meantime.

 

Try this site. Look at the bottom picture and part number 81. I think that is the plug you are thinging of.

[link:www.drivetrain.com/transillm5r1_m5r2.html|Mazda Trans]

Roger Lane

 

On the diagram part number 117 corresponds to the rubber plugs--at least on my transmission. They are at the other end of the top plate.

Marty

 

Something else to watch out for on the Mazda trans, are the shift pins that help locate the shifter ball in the top of the tranny. Also if you ever get the chance to pull the shifter out, check to see if you have the plastic cups in the shift housing. I did not have these in mine. And I think someone else here didn't have those either. That definitely made it much easier to shift once those were back in the hole too!

But my main roblem was the shifter pins had backed out causing the shifter ball to move around in the shift tower.

 

>On the diagram part number 117 corresponds to the rubber
>plugs--at least on my transmission. They are at the other
>end of the top plate.
>
>Marty


My mistake. Thanks Marty, I looked at the wrong end of the case. I took out my Mazda tranny last year and pitched it, so I don't have a reference anymore.

Roger Lane

 

My transmission had one of the steel plugs out but it stayed on top of the transmission. There was, or at least appeared to be, leakage from where the plug was, so I guess that the Mazda trans can leak from the steel plugs too. The transmission shop that replaced my 1st and 2nd shift forks replaced the steel plugs and the rubber ones too so hopefully I won't have these things to worry about. This is the only reason that I know anything about the Mazda trans! I do have some noise coming from my trans in second gear though.

Marty

 

 

My Mazda trans decided to eat itself about a year ago. So I replaced it with a NP435. I do miss the OD, but I know this trans won't fall apart.

Roger Lane