Hi! I've done some searching, but haven't found a situation quite like mine. I hope someone can get some insight.

I bought a Durango about a week ago, a 2000 4.7. At the time it was only throwing a code for the downstream O2 sensor. Replaced that, but the CEL was still on. Scanned it, P0750.

I cleared the code and began to drive the vehicle through the cycle. About 5 seconds into my drive the CEL came back on, same code.

BTW, the vehicle feels slightly underpowered from take off, but everything above 10mph feels great.

So I do research and figure it's the solenoid pack. I take it to a shop for the job because I don't want to screw up anything transmission related. The shop, which has great reviews, does their diagnostic and affirms that it needs a new solenoid pack.

They replace the pack and clear the code, but as soon as he starts taking the vehicle for a drive it throws the same code and the check engine light comes back on. He says it feels like it's missing 1st gear.

The vehicle isn't throwing any other codes. The mechanic told me when he opened up the pan, everything looked very clean (though he did say there was a ton of silicone used as a gasket from a previous service).

So he is stumped. He is recommending a complete rebuild which will cost me about three times what I paid for the vehicle.

Based upon the research I have done, I cannot tell if this qualifies as "limp mode."

I am wondering if it could be the governor pressure sensor.

He isn't charging me for the solenoid pack replacement, as it didn't fix the problem.

Thoughts? Thanks.

 

BTW, the mechanic is telling me that the governor pressure switch is located in the solenoid pack on the 45RFE transmissions. True?

 

I have an 01 Durango 4.7 with same tranny, and recently lost third gear. (A couple numbers higher in code than yours.) My trusty mechanic tried replacing the solenoid pack and cover plate which was damaged, to no avail. I've been driving it for a couple months now in second, keeping it under 45mph (sucks, but it works til I find something else to drive. My guess is the 1st gear clutches are out. Which seems weird to me because I would think 1st is the gear that used the least amount of time. Just out of curiosity, how does it act when you take off from a red light or something? Sounds like it grabs just enough to get you up to second? When mine tries to shift into third, I get nothing, until I put it back down to second gear.

 

Thank you for the response! The "missing of first gear" is so slight that, having never driven one of these before, I just wasn't sure if they didn't have a lot of low end power. There's no abnormal noises or jerking I would expect if it were to suddenly catch.

 

I'm really hoping I can get some direction here.

 

How many miles are on it? I lost 3rd gear in mine at 160,000 miles. 45rfe transmissions are a bit tricky to diagnose sometimes with all the electronics. If it's still fairly smooth and just a bit slow until you get to second gear, I may have been wrong about your low end clutch pack. Sounds more like an electrical problem. If it's got a little higher mileage like mine, you might just consider leaving it alone, and driving it as is. Sounds like once you get past 1st gear, everything is fine. If it's a lower mileage vehicle, it might be worth getting a second opinion from a transmission shop. Don't give up on it though. I've been driving my 01 Durango since 2005, and it's still a daily driver, even with 3rd gear gone. In my experience, the 1st Gen Durango 4.7s are very good vehicles. Mine has been very good to me.

 

I guess I would be considered a shade tree mechanic, I don't take mine to my mechanic unless it's something I'm absolutely stumped on. When I lost third gear, and my mechanic tried to fix it (didn't work), I was all set to pull the tranny and rebuild it myself. UntIl I talked to my mechanic again. He said they are fairly easy to rebuild, but with 160,000 miles, it's going to be a pain to separate the transfer case from tranny, and tranny from engine. He said at 160,000 miles, the frustration of getting it out wouldn't be worth it. If you are by chance like me, have the time, and less miles on your Durango, you might consider that option as well. I guess a lot of it depends on how many miles it has, the condition of the rest of the vehicle overall, etc. Lots of variables to consider.

 

just under 200k.
The problem is I need the CEL to turn off so I can smog it and get current registration stickers.
The vehicle is in great condition otherwise.

 

Very good point...one that I've never thought of. I wonder if they see the code is a tranny issue and not a smog issue, if they would pass it? You stumped me on that one lol.

 

In CA, they won't even run the emissions test until your CEL is off and your vehicle is I/M ready.