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pump noise?

Ok I've been looking around an I think the second sernario on the bottom this page is the same thing goin on with mine. http://sethirdgen.org/tranny.htm Forward sprag? I lose engine braking ability every time I shift to O.D. Except I have first gear with no engine braking in O.D. Does this sound correct?
 
No.

TH700R4's do not engine brake in 4th. That's how they are.

If the forward sprag was shot, you simply wouldn't move in any gear except Reverse.

Does it engine brake in L1 L2 and 3 ranges? (shifter positions)
 
In L1 position I have normal first with engine braking. In L2 I have first With no engine braking(sometimes it works right but not often).In Drive position I have First Second and Third with engine braking. In Overdrive position I have First with no engine braking. If I shift to O.D. at any speed or stopped it drops out of gear and I only have First no engine braking. If I then stop the truck shift to Reverse then to Drive it starts to shift normal again. I feel I should state that my shifter pattern is P,R,OD,D,2,1.

Side note I tore apart the old transmission not a big deal at all, I can't believe the money these guys get to work on these things. I don't think I'll have too much troubles rebuilding one.
 
Ya just about anybody can 'change parts' (rebuild) a trans. The money is in diagnosis, R+R, and 'undo-ing' previous wrong stuff. ;)

So it will not up-shift automatically in OD-4th range?

The fact that stopping then shifting to R and then everything's ok again suggests valves to me. I would investigate the governor valve for sticking, first.

Have you had the VB off the 'new' one?
 
Yes I've had the vavle body off the new one checked the valves that I had diagrams for. I will check the governor.

I have a buddy that took his new 700r4 in to have the output shaft changed so he could run a 205 t.c. it was over $700. thats some bullstuff.
 
I took the governor out everything looks good, valve inside moves when I move the weights. I also took the servo off and found that the inside of the servo cover had never been touched with ATF is this normal?
 
Strange. The 'cover' is actually the bore for the 4th apply piston.. Hmm. It gets it's oil through the center of the pin. What the heck...?

DSC000491.JPG
 
No it oils through the PIN. There is a passage in the case bore where it fits. Starting to wonder if the 3-4 relay or 4th valve is messed up in that VB.
 
You're getting some 'hands on' experience, huh? :D

After first gear, the 2nd gear servo comes on clamping the 2-4 band around the reverse input drum. Better review your 2-4 piston now.

Are you familiar on how to check the 2-4 piston and band clearance?
 
It requires a special tool with the trans out. Trans in, you can get a prybar or a length of pipe, brace it on the frame and press on the nub of the cover. All you're basically doing is pushing the cover, clip in place, inward, which will load the pin against the 2-4 band. This distance should be no more than a 1/8 inch optimally.

Since this trans has been 'hot rodded' who knows how it's set up.
 
This distance should be no more than a 1/8 inch optimally.
Click to expand...

correction, no more than 1/4" optimally. With trans in and on the bench, you can special tool known as a screw driver too. :)
 
I pulled the valve body changed the 3-4 relay, 4-3 sequence valve, and spring out with the ones from the old trans moved freely no obstructions. I did changed valve body gaskets and checkball locations for the B&M kit and it hasn't dropped out of gear yet, I've only driven a few miles though. Still no 4TH.
 
The last time I had a nagging 'no 4th' deal it was one of the VB block off plugs mentioned earlier in the thread. I beat my head on the wall cheking this that the other.. When you said the 4th servo piston was dry, there has to be a reason for that.

Other culprits for no 4th are low pressure, ill adjusted TV cable, and a worn TV bore in the VB. I can't remember off the top of my head but there are a few more.. but I need to look at my book. Seems like 4th servo piston isn't even getting pressure sent to it.



Does your throttle valve look anything like this by chance? (black spool on right)

TV.jpg
 
No, I believe my throttle is stock I think the valve body was stock. Just a rebuild with a, I think, Jet brand servo. I have done a little more driving and I have 1,2, and 3 in O.D. position. Don't know why but I'll take it! Since I now have all gears but fourth I will once again give a little slack to the tv. cable cross my fingers and do an indian transmission dance kick it twice and drive it like I stole it.
 
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