1st Gear Slips Out

I just bought a 1994 4.0L ranger manual. It dose have a short list of problems, but one of the bigger ones is that it will not stay in 1st gear. The motor itself runs smooth and all of the gears feel fine. It dose fine in 1st gear if you hold it in place but as soon as you let go it will pop out of gear. It only dose this in 1st gear. I was wondering what would be the best way to fix this problem.

Welcome to TRS

Bookmark this page: http://www.therangerstation.com/tech_library/index.shtml
Loads of Ranger info there

You will have the M5OD-R1 transmission in a 1994 Ranger.
Very good transmission, Ford used it in all Rangers from 1988 to end of production in 2012.

Slipping out of gear is not a common issue with this transmission.
Most likely cause is that the Dog Gear or 1st gear "teeth" are worn so it no longer locks into place.
Fixing it requires a rebuild.

M5OD-R1 has rubber plugs at the top rear for the shift fork rail installation, as these got old they cracked and allowed trans fluid to leak out.
Trans would start to run warmer as fluid levels dropped causing more wear on the parts inside.
This lead to stripped input gears and other issues, i.e. slipping out of gear.

I would first drain the fluid to see if there are alot of metal fillings in it, this would indicate you should do a rebuild sooner than later.
M5OD-R1 uses Automatic Transmission Fluid(ATF) not 80 or 90 weight gear old, just FYI.

You can often find used M5OD-R1 transmissions as well, fairly safe to go used with these.
But the bellhousing that bolts to the engine is part of the transmission case so it must be from a 4.0l engine.
And if you have 2WD then it must be from a 4.0l 2WD Ranger/Mazda B4000
Or if 4WD then from a 4x4 Ranger/Mazda B4000

In any case replace the rubber plugs with metal ones while trans is out.
1994 is also the last year Rangers used speedometer cables, a newer 2WD trans may not have that hook up, but you should be able to remove and swap tailshaft housings to add speedo cable hookup to newer model trans.
4x4 will have the speedo hook up on transfercase which you are not changing.

M5OD-R1 Rebuild

So I got a used M5OD-R1 transmission that I am going to rebuild but to be honest I know only a little about transmissions. Do you know where a good place to 1. order a good rebuild kit for under $500 is and 2. where would be a good place to find instructions on rebuilding the transmission.

I would inspect it first, see what it looks like inside and if there is any play in the shafts, unless it has 500,000 miles on it is probably good to go

rebuild thread here with pictures: http://www.fordrangerforum.com/drivetrain-tech/20252-ford-m5od-r1-rebuild.html

There are a couple of tools you will need that most don't have, so read thru the article to see what you need.

M5OD-R1 is also called M5R1

ebay is a good place to look for kits

Rebuilt M5R1 goes for $850, so you should be well under $500 unless major parts need to be replaced, i.e. gear clusters and input shaft

RonD said:

I would inspect it first, see what it looks like inside and if there is any play in the shafts, unless it has 500,000 miles on it is probably good to go

rebuild thread here with pictures: http://www.fordrangerforum.com/drivetrain-tech/20252-ford-m5od-r1-rebuild.html

There are a couple of tools you will need that most don't have, so read thru the article to see what you need.

M5OD-R1 is also called M5R1

ebay is a good place to look for kits

Rebuilt M5R1 goes for $850, so you should be well under $500 unless major parts need to be replaced, i.e. gear clusters and input shaft

Click to expand...

It is only called the M5R1 by people who are too LAZY to type the additional characters...

If I see anyone call the "R2" transmission for the F150 an "M5R2"
I will drive to their house and give them a proper bitch-slap, IF they wake up
they will find a typed note telling them that "M5R2" is the manual transmission for the Thunderbird Supercoupe.

You cannot abbreviate Abbreviations.
You also cannot abbreviate acronyms.

Please don't try.

Now as to the specific issue with the transmission being discussed, my opinion if that the issue is most likely a worn shift fork, this is usually caused by someone who habitually rests their hand on the shift lever.

BUT there is a remote possibility that the transmission as a grotesque abundance of excessive main-shaft endplay which in turn is most likely caused by a worn "center" bearing retainer.

Main-shaft end-play normally causes more issues in either 5th or reverse gear... but in any event the only way to know for sure is to drop it out open it up and look...

If it IS the shift fork, I'll tell you right now that I have personally only ever replaced ONE, not that I've ever found one bad one, it's more a case that I mostly disassembled transmissions and built transmissions out of carefully inspected used parts and only used new bearings, seals and syncro rings and generally had a surplus of complete top cover (shifter) assemblies....

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