History:
When I got the Breakaway, it had 75K miles on it. First thing that I did was a complete change of all fluids, hoses, belts and plastic parts. When I got to the MD3060, I found that the filters had a 1993 date code on them furthermore, there was no evidence that the tranny fluid had ever been changed since new. for sure the filters had not been changed. The original oil change requirement for this transmission was a change at 5K-10K mile and then every 25K mile thereafter.

I changed filters and switched to synthetic oil. One other thing that I noticed was the the shift from 3rd to 4th was lazy and a bit slow. The engine did not speed up during the shift ( called a breakout) it just took it's time. All other shifts were fine and crisp. If I had the peddle to the floor during the 3rd-4th shift, it seemed better. I changed oil and filters 3 times to purge all the old oil out!

Checking with a number of Allison techs seemed to confirm that nothing was serious as long as it didn't breakout.

Last year I had a breakout going from 3rd to 4th, just once but it was noted. During this trip to Texas I had another breakout and then on the return I had two breakouts. It is interesting to note that even though I had breakouts, once the transmission had completed the shift to 4th, not further issues, no slippage etc.!

Shifts from 5th back to 4th are very firm.

It certainly looks like I am headed for a tranny rebuild but no one seems to have an idea how long this will go until I need it or if I will get stranded on the road. All the techs I have talked to since my return have indicated that if I anticipate the shift from 3rd to 4th, and let up on the throttle to complete the shift quickly, it should go for a long time. Hmmmm.

It is noted that if it takes longer than 2 seconds to complete the shift into any gear it will go into 3rd ger and lock into "limp home" mode. I would have to stop and shut down to reset and then go on, Not real convenient for sure.

I am having the TCU reset to factory default tomorrow and then drive it for a bit with my driving style so it can learn my demands. Maybe that will help with some of the issue but I doubt it. I wanted to tow the Amigo to the GTG but I think I would rather take it a bit easy until I know for sure what is up.

I have to get to Mojave and then at least back to Texas, after that I have time to dink with it.

More later

A bit more on the MD3060 6 speed. Went looking for the programing connector and could not find it!!

It is a 12 pin gray colored connector with 4 wires.

I looked under the side where the shift panel and ECU is and there was no connector there. I looked in the electrical box on the drivers side and it was not there.

I was assured it was very close to the ECU shifting panel, BUT there was nothing there. I finally traced the cable from the ECU down into the electrical box and found a small cable branching away right where the main cable enters the electrical box. HOWEVER, that cable went outside the electrical box.

Crawling under and sure enough, there it was!! the worst possible place for an electrical connector to be located! Just ahead of the front wheel and will get all of the wheel spray and crap from the road! I had seen this connector before and it looks just like an OBDII connector and because I have the diesel I dismissed this as a universal cable that could be on gas power rigs.

I freed the connector and pulled it back into the box and then when I opened the connector it literally fell apart. Severe corrosion had set in and the +12VDC wire had separated from the connector. Obviously there was some electrolysis going on between the +12VDC pin of the connector and the other pins!!

I went to the local transmission shop which is part of a truck salvage yard and they had a ECU programming connector that had been taken out of something.

Back home I spliced the cable with the new connector and mounted the connector inside the electrical box in a nice dry location. I will post pictures later. Tomorrow I will go to have the ECU reprogrammed to original factory programming and let it learn my driving style. I am hoping that this may solve the lazy 3rd-4th shifting issues.

I asked the tech whether a small amount of voltage leakage from the +12VDC to the adjacent pin could have had any effect on the ECU programming or operation. He didn't know but I think it is very possible. I had other experiences with this sort of problem with Kenworth T2000s that I owned.

Certainly I would advise all owners of Barth with the MD 3060 to verify where the gray programming connector is. If it is where mine was, I can say that this would lead to transmission trouble in the future. The PO did replace the ECU before I bought this Breakaway, Whether the connector location had any thing to do with this failure I can not say, BUT it certainly is possible.

MORE LATER