JD TC54H Tool Carrier transmission no forward drive

[tool_king]

Hi Guys
Working on a JD TC54H Tool Carrier transmission with no forward drive for a friend . Loader serial is DWTC54H576781 Owners guys tried a new FNR handle .Being the loader does a like of forward /reverse all day long . But no luck .Loader had codes 1653 for no ccu transmit ,599 for coolant temp 396 trans oil temp high and 478 oil pressure circuit voltage low .
The guys replaced the trans cooler thermostat already . Was able to clear the codes but the 1653 is still their .Went throught the wiring all seem to to be good on continuity from dash display to trans controller and to loader controller . Even tried spare controllers and dash display from another loader .
Did pressure checks forward low clutch has 244 psi and forward high clutch has 0 psi .
Anyone ever run across this ?
thanks
Ed

 

[mg2361]

To clarify, it moves in reverse OK? Will work in reverse 1st, 2nd and 3rd? No forward in any speed setting?

Do you have pressure to the K1 (1st speed) clutch in 1st forward?

F1653 code for the CCU is generally a nuisance code and can be ignored.

 

[tool_king]

To clarify, it moves in reverse OK? Will work in reverse 1st, 2nd and 3rd? No forward in any speed setting?

Do you have pressure to the K1 (1st speed) clutch in 1st forward?

F1653 code for the CCU is generally a nuisance code and can be ignored.

Yes no forward at all in any gear .Reverse is good .If you put in forward and try move it will no go .But after you put in natural it will roll forward on it's own for couple of inch .Like built pressure then released it .
Would K1 be test port 3 ?

 

[mg2361]

If you have pressure to #9 with the trans in forward 1st, then I am guessing you are getting nothing at test port #7 (1st speed clutch) as well as ports 10 and 8 (2nd speed, and 3rd/4th). Let's see if you have anything at port marked 7 in 1st Fwd.

 

[tool_king]

If you have pressure to #9 with the trans in forward 1st, then I am guessing you are getting nothing at test port #7 (1st speed clutch) as well as ports 10 and 8 (2nd speed, and 3rd/4th). Let's see if you have anything at port marked 7 in 1st Fwd.

View attachment 279111

Thank for the reply . Will stopping back there tomorrow to check out .

 

[tool_king]

If you have pressure to #9 with the trans in forward 1st, then I am guessing you are getting nothing at test port #7 (1st speed clutch) as well as ports 10 and 8 (2nd speed, and 3rd/4th). Let's see if you have anything at port marked 7 in 1st Fwd.

View attachment 279111

Ok so at port 7 in forward 234 psi . Port 9 1 gear you have 250 psi ,Port 10 244psi 2nd gear ,port 8 3rd gear 50psi at idle and 50 psi at 2050 rpm . 4th gear started out at 181 psi then down to 74 psi then it dropped to 53 psi .

 

[mg2361]

FYI, all pressures should be checked at 1500 rpm @ 176*F+. That is what the specs are written around.

Port 7 should have been roughly the same as port 9. Even so, I would think the machine would have moved in 1st with those pressures.

At 1500, and warmed up, check pressure at port #13. Shift through all the gears. That pressure should remain within 4 psi through all the gears. More than 4 psi and there is excessive element leakage, which I already suspect in.

Has the filter been cut open and inspected for debris/clutch material? If not, I would.

You might want to reach out to @Bigbert. He is the resident ZF expert.

 

[tool_king]

FYI, all pressures should be checked at 1500 rpm @ 176*F+. That is what the specs are written around.

Port 7 should have been roughly the same as port 9. Even so, I would think the machine would have moved in 1st with those pressures.

At 1500, and warmed up, check pressure at port #13. Shift through all the gears. That pressure should remain within 4 psi through all the gears. More than 4 psi and there is excessive element leakage, which I already suspect in.

Has the filter been cut open and inspected for debris/clutch material? If not, I would.

You might want to reach out to @Bigbert. He is the resident ZF expert.

So here update what we got on this nice 22 degree day afternoon . I used the analogue gauge instead the digital to get better reading from the bouncing .
Port 7 220 psi at 1500 rpm
Port 9 1st gear 30 psi at 1500 rpm
Port 10 2nd gear 205 psi at 1500 rpm
Port 8 3rd gear 215 psi at 1500 rpm
Port 8 4th gear 220 psi at 1500 rpm
I got the trans up to 174 degrees to make pressure checks .While doing this .I felt the trans make like clunk and I was able to drive forward and back up multiple times with out any issues . Makes me think something was stuck .
I was not able make the pressure check on port 13 do to not having the right fitting to fit the plug port being it is about a half inch .Do you happen to know what size they use on that hole ? I was going see if the book had anything on it .
The guys are going to drain and replace the oil tomorrow .I told them to drain into nice clean pan so we can see what it looks like . And to save the filter with the oil in it so I and cut it open and look at it .

 

[mg2361]

Port 9 1st gear 30 psi at 1500 rpm

If this was in 1st forward, then you have an issue with Low range forward clutch. The other pressures are low. Definitely check the filter. If you have the manual, then perform the leakage test that is in the manual (see below). The pickup in the transmission might be plugged up with clutch material. I think it can be seen through the drain plug while the oil is out. A transmission pump flow test would confirm pump integrity, but there are special tools to perform that test.

If #9 was 30 psi in forward, was the FNR tested to see if it is sending good electrical signals to the solenoids?

The fitting size I believe is 7/16 - 20 M 37° x 14 M x 1.5 ORB