Daveinet

Update:
The after market trans controller did not resolve the issue. At first I thought it was working fine, but after about 50 miles of freeway driving, it started getting very flaky. The speed readout on the controller would climb up to about 50 mph or so, and then as I sped up more, it would start counting back down, so when I was doing 70, it read 40 mph. Of course then it kept switching between 3rd and 4th. I nursed it to the nearest exit. Found a Radio Shack, bought some switches, and wired up a manual shift box. I also hooked up the TC command again and drove 450 miles to home.

So, finally got underneath it to try to figure out why this has been so flakey. I assumed that maybe the speed sensor was weak, so I was going to swap front and rear sensors. Just for grins, I stuck my finger in the rear hole, and to my dismay, there is no reluctor ring. There is another gear right next to where the reluctor ring goes. The sensor was reading the other gear, but because it is a long way away, the pulse is very weak and erratic. OK, so this is BIG UGLY. To fix it, will require a complete trans tear down. It was all I could do to get the trans into the bottom of the vehicle, I just can't imagine doing it again. What is most frustrating is that I specifically asked the shop that built the trans to make sure to install the rear reluctor ring. They did not do it. I will be calling the shop tomorrow morning, we will see how that goes.

Six_Shooter

iTrader: (2)

You can likely install the ring while in the vehicle, by removing the tail housing and after heating the ring (boiling works well), slide it on to the shaft.

71403

There were some 80E 4x4 apps that put the TOSS in the xfer case, never had one to inspect. Supposedly had ring on the output shaft also, with a dummy plug for sensor.

IIRC old (73-up) body style 1-ton, eg 91-93? R/V 3500 chassis. Might be worth seeing if those xfer case parts could go into your v-drive and save the output shaft R&R.

I'd wonder what else trans shop left out since they can't open an ATSG manual for 2 minutes or listen to the customer.

Daveinet

The ring is inside the trans, not inside the tail housing.

I have thought through what could be done with the chain case. Really, there is no space for anything other than the chain and bearings. There are setups that mount to the drive shaft, but the chain case is is not 1:1, so the ECM will not like the wrong ratio. That is already proven by the fact that it is already reading the other gear with less teeth. It is able to read the weak signal, but won't go into lock up and shifts hard, because it assumes there is slip between the input and output.

71403

If you can find a 40ppr driveshaft/pinion mounted sensor just change the gear ratios in the calibration. Or run the PCM in 4wd and program in your xfer case ratio.

Plenty of people running 4L80E's with aftermarket low-gear sets, that's how they keep the PCM happy.