My dads 98 two wheel drive Ram developed a hiccup this morning.
He said that it starts off in 3rd gear but he can manually shift from 1st to 3rd and still drive it.
The only thing that has been done to the truck recently is that he washed it the other day and yesterday he waxed it, nothing mechanical.

From what I know I need to check a few things:
-Check fluid level/color/smell
-Read the codes, if any.
-Check all the wiring going to the transmission for damage and give all the plugs a shot of contact cleaner.
-Check the TV cable for proper alignment.
-See about going to the transmission shop for their free diagnostics so they can read the governor pressure while driving.
-Change the governor pressure sensor/solenoid/transmission fluid/filter if the transmission shops scan tool shows incorrect pressure.

Am I on the right track or is there a miracle cure available that will save me some time?

 

I think you pretty much got it covered there. I think the trans is in limp mode.... so, something went screwy. Since it happened right after he washed it.... that's where I would start.

 

I think he drove it one time after washing it. He waxed it yesterday and then the next time he ran it (this morning) is when it was starting in 3rd.
I thought limp mode was 3rd gear only and it couldn't be manually shifted through the gears. But if it was a wiring/sensor issue that it could be manually shifted.

I read one thread where a guy had some wiring going to the transmission chewed up by a dog and he fixed that and all was good. The later on he had the same symptoms as my dad and it turned out to be a sensor was unplugged.

 

If he can shift manually, with no problems, and it tries to start out in second or third- it is definitely in limp mode, and 99% probability of being either the speed sensor or govenor pressure solenoid..

you're a half hour out from having it fixed once the parts are in hand.. It's a messy dang job though, if you don't have a drain plug installed on the pan.. I think I'd be putting one of those in if'n I was you..

 

I've had my pan off so many times that I can pull it and only get a little bit of fluid on my fingers from where I grab the pan to let it down. It requires a steady hand and taking the right bolts out while leaving the right bolts in to let it drain a little before dropping it.

He just needs to get the truck home so I can check it out, he doesn't get off work till about 5.

 

The fluid is good and there are no codes.
He told me that it doesn't screw up until he is almost at work which is about 25 miles.
I'm going to have him pull it into his shop after work tomorrow (concrete floors and a roof, it's been raining a lot lately) to check out the wiring and clean all the connectors with contact cleaner.
I'm also going to see if he will take my moms truck to work on Friday so I can take it to the transmission shop to get the governor solenoid pressure read.
If that doesn't turn anything up then I guess I'll change out the governor pressure solenoid and sensor. I would think that the speedometer would be affected if it were the speed sensor in the transmission.

 

It may sound goofy, but I came across problems like this where it turned out to be a crank position sensor going bad. If your scanner has live data, watch for the rpm to be unsteady by 100rpm or so, O2's will be up and down at a fast pace, and your advancement will be up and down from 6 deg to 20 deg and back.

 

I'll keep that in mind if the speed sensor doesn't fix it.
He inspected the wires today and when he was fiddling he must have made better contact with the speed sensor because he got a CEL on the way home and it turned out to be the transmission output speed sensor. So hopefully changing that will fix it.

 

Speed sensor on the transmission fixed it. He said it's shifting beautifully now.