M5odr2

[Socnarftrucks]

Thanks Gary!! Too late, I’ve already
Drilled the holes and it was a real pain. Wish I had known about the  E3TZ-7K509-A support…

[Rembrant]

ArdWrknTrk wrote

You want an '83-'87 master with the two bolts one above the other.
Later masters have the bolts on the diagonal and the embossed firewall isn't laid out for these.

I went through this a few years ago. Nice thing is that other than the diagonal bolt pattern, they're identical. The embossed firewall only showed up in 1983, so an earlier truck it will just be smooth.




I installed one in a 1980 cab. Drilled the holes and it worked just fine. I basically made a homemade small bracket:

[ArdWrknTrk]

Right. You made one, but there's a reason the E3TZ and E7TZ firewall braces are different.
And that is because the master cylinder studs moved so the brace is punched differently.

[Rembrant]

ArdWrknTrk wrote

Right. You made one, but there's a reason the E3TZ and E7TZ firewall braces are different.
And that is because the master cylinder studs moved so the brace is punched differently.

 
Oh interesting, I didn’t know they were different. The aftermarket ones all fit both don’t they? I installed the big one from Terrapin in my ‘84, and removed the small one that was in it. By the time I did the 1980 I just made the small one.

[ArdWrknTrk]

I honestly don't know about the ones Terrapin made.

I made the mistake of ordering the E7 version of the small reinforcement from the dealer thinking "I've got an '87!"
But no....  

I suppose just like the 460 EFI heads that were E7TE and went onto '88 model year trucks, starting in September after the lines were retooled.

[86 1/2 Brutus]

I may have the driveshaft, i think if i remember correctly my  parts truck has that transmission and is a single cab short bed 88

[Socnarftrucks]

Just verifying: M5ODR2 transmission came out of a 93. I have installed the concentric save cylinder, master cylinder, and line for a 93. Bleeding (even bench bleeding)and adjusting the clutch has proven very challenging and frustrating
….

[Gary Lewis]

Yes, bleeding these hydraulic systems is frustrating.  You can't seem to get all of the bubbles out, probably because the lines are so small.

Some said to hang it on a ladder to let the bubbles get out.  But I already had it installed.  So I bled it until I could get enough clutch action to drive it.  Had the clutch to the floor to start it and the truck moved but the engine started.  Drove around the neighborhood pumping the clutch and pretty sure the bouncing allowed more movement.  Finally all of the bubbles were out.

[Socnarftrucks]

Thanks Gary! I will remove the MC again and
Bench bleed it hangin on a post or a ladder and gently tapping on the line too. First and reverse didn’t engage
last time so I might have to push it out and try your bouncing method.

[Gary Lewis]

The problem I had was that I couldn't disengage via the clutch.  So I started it in gear, albeit with the clutch on the floor to run the starter.  But I could drive it, slowly, in 1st gear.

[Socnarftrucks]

I’m officially throwing in the towel….. just cannot
Adjust the hydraulic clutch. I have tried every
Trick and tutorial to no avail…. I’m willing to pay
Someone to adjust it for me. I’m in San Antonio, TX

[Rembrant]

Socnarftrucks wrote

I’m officially throwing in the towel….. just cannot
Adjust the hydraulic clutch. I have tried every
Trick and tutorial to no avail…. I’m willing to pay
Someone to adjust it for me. I’m in San Antonio, TX

What do you mean that you cannot adjust it? Do you mean bleeding it?

I've installed a couple M5OD 5spds but I do have a continuous vacuum bleeder which makes things like brakes and hydraulic clutches much easier to deal with.

[Socnarftrucks]

I have bench bled the MC (twice) then bled the
Concentric bearing by gravity (twice) by opening
And closing the Bleeding screw while someone keepers the reservoir full. Tried this method by pumping the clutch and also without…

Tried to aspirate bubbles through the MC reservoir. I have half a clutch that stays midway after pressing fully and then releasing.

Forgive my ignorance: What is a continuous vacuum bleeder ? Is it the gun like contraption?

[Rembrant]

Socnarftrucks wrote

Forgive my ignorance: What is a continuous vacuum bleeder ? Is it the gun like contraption?

I call it a continuous vacuum bleeder, but it's a homemade affair. I put what is called a vacuum ejector on the cap of a pickle jar and connect a compressed air line to it. I then have a line I can attach to a bleeder screw, and then it applies full vacuum for as long as I need it to, hands free. I saw one somewhere...forget where now, but just made a cheap copy. I use it for brakes, hydraulic clutches, etc. It makes things much easier when working alone.

Have you adjusted the master cylinder pushrod?

[Socnarftrucks]

The MC, CSC, and Line are for a 93. The MC pushrod is non adjustable unlike the 84 and up. I wonder if I have to have a MC for a  84-86…..

[Rembrant]

Socnarftrucks wrote

The MC, CSC, and Line are for a 93. The MC pushrod is non adjustable unlike the 84 and up. I wonder if I have to have a MC for a  84-86…..

The factory pushrods were not adjustable that I'm aware of. The only adjustable ones I've seen were the aftermarket ones that come with some new MC's.

I'm not familiar with the '93 up master cylinders. I think they're different than the 84-86, and 87-92 versions. I'm sure the bore/stroke is the same, but otherwise they are different.

Of the two M5OD swaps I did, I used new 1984 replacement MC's both times, and ordered the slave cylinders and hydraulic lines for 1991 models. I don't know if it makes any difference or not.

[Socnarftrucks]

SUCCESS AT LAST!!! The issue was with the stroke length of the pushrod! I installed the original 93 MC and an aftermarket adjustable pushrod.  After some trial and error with the length of the pushrod, the transmission shifts nicely now and the clutch pedal returns fully when released.  This was a huge learning experience with some very frustrating segments. With all the information on this thread and all the lessons learned, I highly recommend the transmission swap as the truck feels a lot lighter now!   Thanks to all who chimed in, couldn’t have done it without all of you.

[grumpin]

Socnarftrucks wrote

SUCCESS AT LAST!!! The issue was with the stroke length of the pushrod! I installed the original 93 MC and an aftermarket adjustable pushrod.  After some trial and error with the length of the pushrod, the transmission shifts nicely now and the clutch pedal returns fully when released.  This was a huge learning experience with some very frustrating segments. With all the information on this thread and all the lessons learned, I highly recommend the transmission swap as the truck feels a lot lighter now!   Thanks to all who chimed in, couldn’t have done it without all of you.

[Gary Lewis]

Excellent!  Glad you got it figured out.