Engine/Transmission (1998.5 - 2002) transmission action up

[dcoffman]

Transmission is not shifting out of frist properly . After it gets out of frist it shifts fine ,when I stop next time it hangs in frist. This is in a 99 with a 47re.

Thanks

 

[JLandry]

Try replacing the transmission output shaft speed sensor located in the transmission tail housing. It's an inexpensive part and should be available at any auto parts store. It's simple and quick to replace.



If that doesn't solve the problem report back and we'll help you trouble shoot the problem.



Do you change the transmission fluid, filter, and adjust the bands on a regular basis?



Best regards,



John L.

 

[dcoffman]

Try replacing the transmission output shaft speed sensor located in the transmission tail housing. It's an inexpensive part and should be available at any auto parts store. It's simple and quick to replace.



If that doesn't solve the problem report back and we'll help you trouble shoot the problem.



Do you change the transmission fluid, filter, and adjust the bands on a regular basis?



Best regards,



John L.

He changed fluid and all 1 month ago.

Thanks I'll let you know what he does.

 

[dcoffman]

changed the sensor no change,checked at auto zone-no codes,any ideas

 

[JLandry]

OK... some questions:

1. Did the problem start gradually, or just suddenly begin?

2. Does it happen every time the transmission goes back into 1st gear, or only occasionally?

3. What *exactly* do you do to get the transmission to shift from 1st to 2nd gear? I. e. : Does it finally shift on it's own when the truck speed gets high enough or do you play with the throttle and/or gear selector?

4. Were the bands adjusted when the transmission fluid was last changed (you didn't specifically say when I asked before)?

A delayed shift from 1st gear could be caused by a number of things:

1. Mis-adjusted (loose) front bad
2. Mis-adjusted gear selector linkage
3. Faulty governor pressure sensor
4. Faulty governor pressure solenoid valve

Best regards,

John L.

 

[dcoffman]

bands were adjusted and vavle was changed in vavle body to stop tc from draining,and t pump fliuld in park. The thing was shifting fine last night got 2 inches rain and this morning its acting up,to get it to shift you have to ease off throttle around 23mph and it will finally shift

 

[JLandry]

The thing was shifting fine last night got 2 inches rain and this morning its acting up

Well if this just started after all that rain, it sure sounds like it could simply be water in an electrical connector. The PCM (Powertrain Control Module) controls transmission shift points electronically via the governor pressure sensor and pressure solenoid. If moisture were causing a partial short to ground, etc. , that would do it.



There are two connectors on the driver's side of the transmission that you might want to disconnect, clean, dry, and then lubricate with silicone grease before reconnecting. One is the backup light switch and the other is for the governor control circuit. Also make sure the three PCM connectors are clean and dry. The PCM is on the passenger's firewall under the hood.



John L.

 

[DACoffman]

ok thanks John I'll check that in morning I left truck at dads,Love the truck but not much on the slush box lol.

Thanks again,Woody

 

[dcoffman]

changed gov pressure solenoid and sensor checked bands and checked all grounds again still not shifting properly.

Woody

 

[JLandry]

changed gov pressure solenoid and sensor checked bands and checked all grounds again still not shifting properly.

Woody,



One of my next suggestions would have been that maybe you had a bad governor pressure sensor or governor pressure solenoid... but since you say you replaced them again, that tends to rule them out as being the cause.



Another source of this problem could be there's something wrong with the front band or the servo which actuates it. The shift into second gear (either automatically or manually) is accomplished by the front band being applied.



Question: Does the transmission seem to downshift into 2nd gear normally, or could it be skipping over 2nd and going from 3rd to 1st when you're coming to a stop?



Other than that I'm fresh out of ideas except you might wan to try adjusting the gearshift linkage. I'm a bit skeptical it'll help, but it sure can't hurt and doesn't cost anything to do. From the service manual:



LINKAGE ADJUSTMENT



Check condition of the shift linkage (Fig. 222). Do not attempt adjustment if any component is loose, worn, or bent. Replace any suspect components. Replace the grommet securing the shift rod or torque rod in place if either rod was removed from the grommet. Remove the old grommet as necessary and use suitable pliers to install the new grommet.

(1) Shift transmission into PARK.



(2) Raise and support vehicle.



(3) Loosen lock bolt in front shift rod adjusting swivel (Fig. 222).



(4) Ensure that the shift rod slides freely in the swivel. Lube rod and swivel as necessary.



(5) Move transmission shift lever fully rearward to the Park detent.



(6) Center adjusting swivel on shift rod.



(7) Tighten swivel lock bolt to 10 N·m (90 in. lbs. ).



(8) Lower vehicle and verify proper adjustment.​

Check linkage adjustment by starting engine in PARK and NEUTRAL. Adjustment is acceptable if the engine starts in only these two positions. Adjustment is incorrect if the engine starts in one position but not both positions If the engine starts in any other position, or if the engine will not start in any position, the park/neutral switch is probably faulty.

 

[dcoffman]

It does skip 2nd gear coming down. It goes into 1st. He's going to check with a transmission shop Monday.

Thanks for all you help

 

[SPearson]

Where is the best place to purchase a new governor pressure sensor and governor solenoid valve? I am getting ready to drop the pan and adjust rear band, replace gov sloenoid and pressure sensor, change fluid and filter, check the torque on the valve body bolts. Anything else I should do while I'm in there trying to sort out my shifting problems? Mine rarely goes into first anymore (even when shifting manually, only goes into second when shifted manually to first. Otherwise, it will stay in 3rd and try to leave the stoplight that way). Thank you for any help or ideas you can give me.

Stuart

 

[JLandry]

Where is the best place to purchase a new governor pressure sensor and governor solenoid valve?

Stuart,



I've had good luck ordering online from Transmission Parts USA.



The parts are fairly common and you should also be able to buy them from your local auto parts store.



You mentioned you plan to adjust the rear band when you have the pan down, but don't forget the front band too. Otherwise it sounds like you have all the basics covered.



John L.

 

[SPearson]

Hi John,

I'll give Trans Parts USA a call. Good prices! I adjusted the front band already because it was external and easy to do using the very helpful information you sent me previously. The shifting in this truck is going to drive me to drinking! LOL. Every time I stop (intersection, red light etc. ) I don't know what gear it's going to try to start out in, when (or IF) it is going to shift to the next gear, or how much damage is being done while I try to sort it all out. The G56 conversion is looking better all the time! Thank you again for all your help John!

Stuart

 

[DACoffman]

the transmission shop found a broke pin stop and the band engaging metal piece was bentshould have back next few days.

Woody

 

[JLandry]

the transmission shop found a broke pin stop and the band engaging metal piece was bentshould have back next few days.

Woody

Thanks for letting us know.



That sort of failure sounds like it could have been caused by someone over-tightening the front band adjusting screw (using FOOT pounds instead of INCH pounds).



Regards,



John L.