Won't shift on to overdrive

[Maraudermike1]

I have a 2003 300A with the 4R40W. From time to time it won't shift into overdrive. The fluid is as clean as can be and when i shut the car off and drive it again it's fine. I'm pretty sure it's electronic. Anybody had this happen to them? Would a tune with a transmission "retime" help at all? What could cause that? Thanks guys!

[MERCMAN]

I have had the same problem with mine. The next time it happens, shift into N rev it a bit and drop it back into gear with OD on. It always works for me

[MrBluGruv]

I would say first you need to adjust the linkage underneith the car, a LOT safer than neutral dumping, aside from the fact that that probably doesn't really do anything to address the real problem at hand. If your transmission has ever had to be pulled out of the car, I can almost guarantee you it's the linkage.

Here's a quick test to see if it's linkage, I was able to isolate it this way myself: if you are in drive and all 3 normal gears shift and engage properly but OD won't engage even when it is enabled and you are in Drive, try nudging the shifter forwards while it's in drive and see if that makes it go. You won't need to go to neutral, just try to kind of force it forward while it's still in drive. If it engages, you need to readjust the linkage under the car, which is VERY simple, you just need stands to get under the car to do it and a rachet to loosen the bolt so you can move the arm.

[Motorhead350]

I have had the same problem with mine. The next time it happens, shift into N rev it a bit and drop it back into gear with OD on. It always works for me

That's exactly what I do.

Be sure when you do this you leave your foot off the gas the whole time. It will be back to normal.

[Canadasvt]

This was repaired under warranty on mine. A solenoid had to be replaced.

[Krytin]

I would say first you need to adjust the linkage underneith the car, a LOT safer than neutral dumping, aside from the fact that that probably doesn't really do anything to address the real problem at hand. If your transmission has ever had to be pulled out of the car, I can almost guarantee you it's the linkage.

Here's a quick test to see if it's linkage, I was able to isolate it this way myself: if you are in drive and all 3 normal gears shift and engage properly but OD won't engage even when it is enabled and you are in Drive, try nudging the shifter forwards while it's in drive and see if that makes it go. You won't need to go to neutral, just try to kind of force it forward while it's still in drive. If it engages, you need to readjust the linkage under the car, which is VERY simple, you just need stands to get under the car to do it and a rachet to loosen the bolt so you can move the arm.

That there ^^^ is right on the money!!!!!:banana2:

[Maraudermike1]

Anybody have a part number on that solenoid by chance? Where is it at?

[Darrin]

My guess is the MLPS (also known as a neutral safety switch at places like Autozone). Cheap and easy. To install you have to have the car in neutral and line up the marks labelled "Neutral" on the sensor and bolt it down.

Darrin

[Brian H]

Hows the shop comin', Darrin?

[Darrin]

I am in the shop and in limp mode but at least I am able to work.

I picked up the final load of insulation and the outdoor HVAC unit yesterday. As soon as I catch up on the paying work it is time to start building walls.

Lots of work to do yet though. LOTS of work. Progress on the shop is happening but it's coming along very slowly. The summer heat in a metal building with hardly any real ventilation has sucked, but it has been do-able so far. I have to get walls up and HVAC in before winter though. No doubt about that.

Darrin

[johnjamis]

+1 on ADJUST THE SHIFT LINKAGE!!