518 46rh help please

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Ges2343

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This is in my 95 ram.

It’s got 2800 stall converter

Red alto power packs in the direct and forward clutches

Reman pump with stator shaft.

Solid front band

3.8 lever

Fresh rebuild with transgo tfod hd-2 kit installed.

I have a no 3rd gear condition. Clunk seems to be there but not shift. 1-2 shift is there but a bit delayed.

I have been through the valvebody twice now to check my work. I have pulled the direct clutch out and re airchecked found the short seal and replaced with the wide inner piston seal.

Air check on both clutches and they are good. Air checked servos all is well also.

Accum/ line pressure is

1st 64psi
2nd 64psi
3rd command seem to drop a couple psi for a split second then levels back to 64psi

1-2 shift at 15mph
2-3 wants to shift around 35mph

Governor pressure

1st 7psi
2nd 14psi cannot get any higher than 14 psi all the way to 50mph.

I dropped the OD housing tonight and checked the governor seals and the governor valve itself. I don’t see anything out of place. Governor don’t seem to be sticking. What else could cause low governor pressure.

I do not have another VB to check with.

Feels like 3rd is a neutral shift

I do not have the OD and lockup solenoids wires hooked up during testing.

Please help as I am lost
 
How is reverse?
Reverse and Drive both use the hi-drum. In reverse, the pressure is unregulated and should be ~240 to 300psi @1600rpm;IIRC

But I agree your governor is not working correctly. The question is; is it the governor or is it the circuit, or is it the 2-3 shift valve or did you forget the #3 check ball .That ball separates the Hi from the reverse. If you forget that ball, hi-drum pressure gets dumped straight into the pan,thru what would normally be the reverse circuit. So check your reverse pressure.
Reverse pressure if intact ( 2 balls; #3 and #2; and a properly detented manual valve,), equals line-pressure, equals pump pressure; usually in the range of 230 to 260 but can be as high as 300@1600rpm. However, line pressure also feeds the TC, thru the TC control valve........ so if the TC is hemorrhaging pressure..................... ; anyway, just check the reverse pressure. Since you have the OD unit off, make sure the governor is properly assembled and that you have the right one for your rear gear and tire-size, and that the flyweight is properly sprung and not sticking..
BTW, you do have your TV pressure cable hooked up and adjusted, right?, aka the Kickdown mech. I'm pretty sure the TF-II still requires it

Happy Hunting
 
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Reverse is firm and solid.

That was one of my reasons of tearing that valve body back apart was to check that ball. I had read that somewhere before.

Will have to get od housing back up and check reverse pressures.

Yes TV cable is maxed out at Wot and loose at idle.
 
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If the reverse circuit pressure is where it is supposed to be and it feels like a false neutral in third AND second is working right, then my guess is that the governor pressure at the 2-3 valve is just NOT sufficient to complete the shift. And your other governor pressures are showing that.
So first thing to do is to make sure the governor weight assembly is not in backwards, lol, that would severely restrict the pressure

Then IMO, either the governor is hemorrhaging or the circuit is. There are no balls to worry about, just the governor support and the two sealing cast rings. Because the ports are rectangular, it is hard to pressure test that rear part of the circuit. But with the tail off, can you just take it all apart and look it over. I haven't had the od-unit off to see how it assembled; but on a 727 after the valve shaft is removed, the only thing that holds the governor house on is that rear circlip. Once out, you can check the cast-rings. It's just a couple of minutes at this point.
 
AJ/FormS said:
If the reverse circuit pressure is where it is supposed to be and it feels like a false neutral in third AND second is working right, then my guess is that the governor pressure at the 2-3 valve is just NOT sufficient to complete the shift. And your other governor pressures are showing that.
So first thing to do is to make sure the governor weight assembly is not in backwards, lol, that would severely restrict the pressure

Then IMO, either the governor is hemorrhaging or the circuit is. There are no balls to worry about, just the governor support and the two sealing cast rings. Because the ports are rectangular, it is hard to pressure test that rear part of the circuit. But with the tail off, can you just take it all apart and look it over. I haven't had the od-unit off to see how it assembled; but on a 727 after the valve shaft is removed, the only thing that holds the governor house on is that rear circlip. Once out, you can check the cast-rings. It's just a couple of minutes at this point.
Click to expand...


Well it’s been busy. Today was the day I pulled the OD housing off inspected the Governor every way imaginable. I even put a sonnax governor valve in it. The new and improved. Put it back together and seen a spike of maybe 35 while goosing it on the lift. Still 14psi at 25mph and no 3rd shift. Then things went all to hell. Dropped the truck down off the lift and went to take it for a spin and nothing forward or reverse. Only a slight creep at 4K snaps. Lifted back up and did line pressure test 0 psi in all gears at idle. Dropped the valve body and air checked clutches huge leaks in both forward and direct. Then all of a sudden forward came alive and checked good after going back and forth. Direct still has huge leak.

These Teflon seals that came with transgo kit. Are they junk? They sit on the stator shaft. What’s your personal preference on cast vs Teflon?

I’m ripping this thing out tomorrow for the 3rd possibly 4th time.
 
I like the teflon/aluminum for the direct; they look like white metal. Is the reman pump identical to the original?
 
I have never used the Teflons,cuz they look like trouble to me. The kits comes with both so I got a box full of unused Teflons around here somewhere.
If you have zero line pressure at the Reverse port, you got big problems. This circuit is unregulated and should read max pump pressure. So check your L/R piston hasn't blown up, then I have never seen the front pump catastrophically fail, so Ima thinking the TC hub drive broke off, or like you are thinking about the seal-rings, or the front gasket. In any case, the only two checks you can do with thrans up there, are the reverse hydraulic pressure test, and air test. And since you have already seen some pressure test failures, I hate to agree with you, but I don't see any way around dropping it.
If anybody out there disagrees, now's the time to respond
 
AJ/FormS said:
I have never used the Teflons,cuz they look like trouble to me. The kits comes with both so I got a box full of unused Teflons around here somewhere.
If you have zero line pressure at the Reverse port, you got big problems. This circuit is unregulated and should read max pump pressure. So check your L/R piston hasn't blown up, then I have never seen the front pump catastrophically fail, so Ima thinking the TC hub drive broke off, or like you are thinking about the seal-rings, or the front gasket. In any case, the only two checks you can do with thrans up there, are the reverse hydraulic pressure test, and air test. And since you have already seen some pressure test failures, I hate to agree with you, but I don't see any way around dropping it.
If anybody out there disagrees, now's the time to respond
Click to expand...


It’s out and the verdict is in. The reman pump assembly bolts were never tighten. They backed out a couple turns. Not allowing the stator assembly to seal against the pump assembly. Now back to the 2-3 shift issue.

Them Teflon seals are getting replaced with the ones in that came with the kit.
 
Guess the reman pump wasn't "identical" to the original...yuk yuk yuk..If ya want it done right ya gotta do it yourself.
 
It’s all back together. As of 10:30 tonight. Test run on the lift says still no 3rd and I think gov pressure is still low because 2-3 shift doesn’t happen until 36mph. At that point you feel it happen then speed starts slowly dropping. At idle I’m at 22 mph in 2nd gear. I’m pretty sure with no pull on tx cable it should shift to 3rd at idle. I have to gas it to get up to about 36mph I feel it hit. Then it slows back down with the pedal held at the same rpm.

The 518 uses 3 non cast rings on the governor so only option I had was to reuse what I had in the kit back there.

I will probably recheck pressures tomorrow if I have some free time.
 
Sounds like the trans is trying to engage two gears at once.l
Governor pressure is also a function of line pressure. If the line pressure is low, so will be the governor pressure.
Line pressure should be same as or close to same as, reverse pressure and runs around 250 unregulated psi at 1600rpm,to 275 max.
In reverse:
If #4 ball is missing, oil will dump into the manual valve cavity and back into the pan.
If #3 ball is missing,Oil will leak into the KD servo and lock it off, no biggie; but oil will also be exhausted at the 2-3 shift valve, so reverse pressure will be low.
In second gear;
neither of these balls is being used.
In drive;
the #3 ball prevents dumping fluid back to the pan via the manual valve. And a missing #3 ball, looks like line pressure could find it's way back into the L/R servo, and maybe drag that band, which would be felt as the car slowing as the trans is trying to engage two gears at once.
If you go back into the VB, you might as well check the shift-valves are installed correctly. I think both of those valves can be installed backwards... And IIRC the Throttle pressure spring can be accidentally swapped for one of the others, I forget which one, possibly the 2-3 shift valve, I forget.
 
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AJ/FormS said:
Sounds like the trans is trying to engage two gears at once.l
Governor pressure is also a function of line pressure. If the line pressure is low, so will be the governor pressure.
Line pressure should be same as or close to same as, reverse pressure and runs around 250 unregulated psi at 1600rpm,to 275 max.
In reverse:
If #4 ball is missing, oil will dump into the manual valve cavity and back into the pan.
If #3 ball is missing,Oil will leak into the KD servo and lock it off, no biggie; but oil will also be exhausted at the 2-3 shift valve, so reverse pressure will be low.
In second gear;
neither of these balls is being used.
In drive;
the #3 ball prevents dumping fluid back to the pan via the manual valve. And a missing #3 ball, looks like line pressure could find it's way back into the L/R servo, and maybe drag that band, which would be felt as the car slowing as the trans is trying to engage two gears at once.
If you go back into the VB, you might as well check the shift-valves are installed correctly. I think both of those valves can be installed backwards... And IIRC the Throttle pressure spring can be accidentally swapped for one of the others, I forget which one, possibly the 2-3 shift valve, I forget.[/
AJ/FormS said:
Sounds like the trans is trying to engage two gears at once.l
Governor pressure is also a function of line pressure. If the line pressure is low, so will be the governor pressure.
Line pressure should be same as or close to same as, reverse pressure and runs around 250 unregulated psi at 1600rpm,to 275 max.
In reverse:
If #4 ball is missing, oil will dump into the manual valve cavity and back into the pan.
If #3 ball is missing,Oil will leak into the KD servo and lock it off, no biggie; but oil will also be exhausted at the 2-3 shift valve, so reverse pressure will be low.
In second gear;
neither of these balls is being used.
In drive;
the #3 ball prevents dumping fluid back to the pan via the manual valve. And a missing #3 ball, looks like line pressure could find it's way back into the L/R servo, and maybe drag that band, which would be felt as the car slowing as the trans is trying to engage two gears at once.
If you go back into the VB, you might as well check the shift-valves are installed correctly. I think both of those valves can be installed backwards... And IIRC the Throttle pressure spring can be accidentally swapped for one of the others, I forget which one, possibly the 2-3 shift valve, I forget.
Click to expand...


My dad called transgo tech hotline today. They wanted pressure off of the front servo. Gauge hooked up went through all the gears and I got nothing. Maybe a 2psi spike @45mph. Called back guy wanted us to look at the VB at the 2-3 shift valve. We looked everything matches the book and the instructions. All check balls checked again for the 4th time.could it be possible that the servo cover is leaking enough to spill out my pressure to release the band?
Click to expand...
 
could it be possible that the servo cover is leaking enough to spill out my pressure to release the band?
Click to expand...
I don't think so. What does the air-pressure test say?

What kindof line pressure are you getting?
The 2-3 shift valve relays pressure to the hi-drum for to get direct third gear. Simultaneously, that pressure disengages second gear. But where does the 2-3 valve get it's pressure from? Why, from the 1-2 valve! at the command of the governor. So if the 1-2 valve doesn't move, the 2-3 will not get supply.With no governor pressure, you will never get third gear. Fix the governor pressure and that will fix the third gear.
The gov circuit is pretty simple, feeding just the two governor plugs and also the shuttle valve. Throttle pressure is supposed to keep the shuttle valve in the closed position. When you do a lift foot shift, throttle pressure drops and if it drops far enough, it will dump the governor pressure. No gov pressure, no third gear.The shuttle valve also seems to do something between the shifts sending fluid to the modulator, so my guess is that it smooths the shift.
OK, but what if there is no throttle pressure? Well, the way I read the diagrams, if there is no throttle pressure, the shuttle valve could be dumping governor pressure full time.
So then the question becomes; do we have throttle pressure or is the shuttle valve stuck open?
Well if you had no throttle pressure, and no governor pressure, the trans would not upshift.
If the throttle pressure only, worked, you would have no 1-2 upshift.
If the governor only worked, you would have a very early 1-2 upshift.
If the shuttle was dumping but everything else was working, you would have a very late 1-2 upshift..............................
So, if the air-pressure test says everything is OK, and the governor itself is working, then Ima looking at the shuttle-valve next.

But I gotta mention that the governor gets it's supply from the manual valve, so if it is not detenting properly, then I suppose the governor may not be getting full line pressure.
That's the best I got
 
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AJ/FormS said:
I don't think so. What does the air-pressure test say?

What kindof line pressure are you getting?
Click to expand...

Air check is good I’m looking at the release pressure on the big bore or the front servo. Air check only checks the small bottom bore, moving the pin up correct?

Last I checked before the 2nd tear down was 65 in forward gears.

Possible timing issues with the rigid front band. I set it at 2 turns out. I found some friction material in the pan so I do think it has some bind. I would still think it would shift with the bind. Correct?
 
Ges2343 said:
Air check is good I’m looking at the release pressure on the big bore or the front servo. Air check only checks the small bottom bore, moving the pin up correct?

Last I checked before the 2nd tear down was 65 in forward gears.

Possible timing issues with the rigid front band. I set it at 2 turns out. I found some friction material in the pan so I do think it has some bind. I would still think it would shift with the bind. Correct?
Click to expand...

Surrounding the accumulator are several holes;including one for the second apply and one for the second release.
I set all servos at 1/4 inch travel.
Like I said, I think the trans while in drive,is trying to engage two gears at once. That is not supposed to happen between second and third, but if it somehow did, that will chew up the band and the drum pretty quick.
There is only one way to engage direct, and that is to physically move the 2-3 shift valve. And only governor pressure can do it. And when it does, it simultaneously disengages second.

BTW, you know about the two different sized balls in that VB , right? The big 3/8 is the hi-pressure relief. and the 5/16 is the front clutch ball-check; that is to say, the hi-drum. All the other 5 are smaller and same-sized. I see by the diagrams that it is possible for hi-drum oil to attempt to engage low servo, if that 5/16 ball doesn't do it's job.That ball also prevent dumping the oil back into the pan...... which would cause a zero-pressure reading on the front servo release. Sometime in the 70s, I think that 5/16 ball was changed to 11/32
 
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Ok, as you can see my time is limited.

Today I went to the local LKQ and pulled a VB. It looks like a virgin that has never been tinkered with.

I came home and put it in. I get 3rd gear at around 50 mph. So I might have a governor issue or a cable issue.

So I’m somewhat happy now. I don’t think I will have to remove the transmission any more.

I have the old VB still laying on the bench and I am trying to find out why it didn’t work with that trans go shift kit. I took it all apart looking and I can not find nothing.

Why is the release port so small in the transgo separator plate? This thing is tiny compared to the one in the original plate. It’s less than .090. Could that be my issues with me changing to the 3.8 kickdown and bringing the spring count up to 12 in the direct clutch.
 
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