Engine/Transmission (1998.5 - 2002) What's wrong with the truck? APPS, trans...

[chlenzho]

Truck had the bad APPS symptoms. Would clear up for a few months after disconnecting the battery and then slowly up and down on the pedal. Lately that stopped working. Bought a filter(NAVONE N-25) for the inline noise, did not cure it. Bought a Timbo APPS, still had the symptoms. One thing I've noticed after reset with both filter and APPS, truck would run great for first 10 minutes. When engine warms up to normal operating temperature symptoms would reappear.



Here is a summary of the symptoms of late.



At start up, engine cold, transmission shifts normal. At normal engine operating temperature (after warm up - 10 minutes running), transmission does not upshift to 3 or 4? Engine speed at 2000+ rpm before shift occurs if at all. Around 30-35 mph vehicle speed. Strange thing occurs at 55+ mph. When gas pedal is released or eased off, transmission downshifts. Doesn't seem to be slipping just erratic shifting.

 

[chlenzho]

Truck is 1998. 5 2500 Cummins, Quad cab. No upgrades.

 

[chlenzho]

Oh and another thing on the above subject. A few months ago the truck has started to whine. Starts at around 20 mph and increases with the engine speed. Not sure if its the tires which needs to be replaced soon. I've noticed that there are loud tires out there. I can't recall if they were loud when new. Question is do tires get loud when they need to be replaced? Or is it related to the above symptoms? Any input would be greatly appreciated. Thanks

 

[BigPapa]

You could have a bad alternator. A bad alternator can cause the problems you mention above and could be the source of your whine. Remove your belt and check all your pulleys to locate the whine. Have your alternator tested and ask them to pay particular attention to the ripple.



Scott

 

[cerberusiam]

Have you changed transmission fluid and filter lately? The whine could be a plugged filter, or, a planetary going bad.



Typical shifting problems like that centers around the gov pressure solenoid and transducer. They can be changed by dropping the trans pan. Check your output speed sensor also on the trans OD unit if you have one. If they get crud on them it will foul up the signal and cause shift issues.

 

[chlenzho]

Had the alternator tested today at O'reillys where I bought the part last february. It passed. According to the tester, ripple test was good. Might have it done again just to be sure. They tested my starter before said it passed ended up being bad. I found an article on the internet on performing a ripple voltage test using a DMM. My meter reading came out to . 01 volts. thanks Scott (BigPapa).

 

[chlenzho]

Cerb, how can you check or test if a governor pressure solenoid is bad? And where is the output speed sensor located? I have a 47RE transmission. Does it have one? Didn't know a clogged filter could cause the whine. The whine starts at around 20mph and goes up from there. Hoping its the filter which I can replace and not the planetary. Is there a way to see if its clogged? Thanks for the info.

 

[cerberusiam]

Cerb, how can you check or test if a governor pressure solenoid is bad? And where is the output speed sensor located? I have a 47RE transmission. Does it have one? Didn't know a clogged filter could cause the whine. The whine starts at around 20mph and goes up from there. Hoping its the filter which I can replace and not the planetary. Is there a way to see if its clogged? Thanks for the info.

Not sure when the output speed sensor was implemented so check the driver side of the OD unit for a sensor that would be in about the the same place as a speedo connection.



You can check the gov pressure by tapping a gauge into the test port and watch the pressure as wheel speed increases. The increase should be smooth and run 1 psi for every mph up to about 55 mph. If the solenoid and transducer have never been replaced its time to just replace and go from there.



If you haven't changed fluid and filter for a while do it. Check the pan for metal and change the gov solenoid, transdcuer, and filter at the same time. Need to check your front band setting at the same time to verify it is correct.

 

[chlenzho]

Don't know if the solenoid and transducer have ever been replaced. It has 330k miles. I've put in half the total miles since bought used. Runs great except for the shifting. I've ordered the solenoid, transducer and filter. Got a good price on it. Hope that fixes it. Crossing my fingers. Thanks for the info.

 

[chlenzho]

when checking the pan how much wear is to much...

 

[cerberusiam]

when checking the pan how much wear is to much...

Drain as much fluid as possible but don't dump the pan. You want a 1/4 inch of fluid in the pan to see whats actually there. A black sludge coatingthe bottom of the pan is pretty normal as long as its not super thick.



The stock steels will make metal and buildup around the magnet so black goo there is normal. The frictions will always shed a little and the heavier stuff settles to the bottom of the pan as dark coating.



Look for pieces of silver metal shavings or brass in the pan. More than just a few is a bad sign. Also, look for flakes or chunks of friction material. When those are present its not a good sign.



The gov transducer/solenoid and output speed sensor are sensitive to the metal the trans makes stock. Then simply don't work well after so long and a build up. About 40k is all we are getting in the newer trucks before ****ing issues occur.

 

[chlenzho]

I have a pic of the pan but unable to post it. There was quite a bit of material on the magnet. Found small amounts of very tiny silver metal shavings, but no brass. Went ahead and replaced the governor solenoid, transducer and filter. Adjusted the band. Took it for a test drive. Drove great until engine temperature went up and someone tailgated us. I've noticed that the erratic shifting occurs at normal engine operating temperature. Soon as the needle hits 180 degrees. Don't have a temp gauge on the transmission. The transmission warning light has never come on so I'm assuming it's not overheating. Is there anything else I could check? And if the transmission was bad would it be affected by temperature?

 

[cerberusiam]

And if the transmission was bad would it be affected by temperature?

Yes it could. Both the direct clutch pack and the OD clutch pack rely on seals to apply correctly. Cold the seals is stiff and will hold even with wear. Once it warms up the wear is too much and the seal won't hold when pressure is applied. Wrap the rpms and the pressure goes up and it eventually shifts because there is now enough pressure and flow to apply the clutch pack.



It is a possibility with your symptoms.

 

[chlenzho]

When I unplugged the electrical connector on the speed sensor, transmission fluid started dripping down from inside the sensor. Is that normal? Is that the gunk your talking about affecting the signals?

 

[cerberusiam]

When I unplugged the electrical connector on the speed sensor, transmission fluid started dripping down from inside the sensor. Is that normal? Is that the gunk your talking about affecting the signals?

Yes. Neither the speed sensor nor the trans control harness should have fluid in the electrical connector.

 

[chlenzho]

I just tried to remove the speed sensor but had to install it back in. I guess I should drain some fluid from the transmission first. Thats normal right. If I lift the rear of the truck then remove the speed sensor will that help with the fluid overflow.

 

[chlenzho]

Pulled out the old speed sensor. I see what you mean about gunk as the tip was full of it. Bought a new speed sensor, installed it then test drove the truck. Very disappointed. My only recourse now is to take it to a transmission shop. How long do these transmissions last by the way. I have 331k on the odometer. Put in half that since bought used in 2006. I don't know if the previous owner had ever replaced the transmission. With proper maintenance how many miles before a 47re needs to be replaced or rebuilt?