2005 Auto 5sp won't stay in "low" (1st gear)

I have done a bunch of googling and no luck, thought I would try here.

I have a 2005, 4x4, 4.0 with 5pd auto. The gear selector has been a little temperamental for example i can occasionally put it in a lower gear (when coming down a mountain for example) and it will hold that gear. Other times it is like the truck doesn't sense what position the selector is in (the dash light gear indicator also turns off) and then it will and won't back and forth.

I took the shifter apart and sprayed from WD-40 on the parts that looked lubricated which may have helped resolve that issue.

However, the truck will not sense that it is in "low"aka 1st gear. Instead it senses 2nd gear. I'd like to be able to hold in 1st for slow wheeling. Any thoughts? Do I need a new shifter assembly? Thanks

 

Don’t think they are designed to stay in first gear, only in 4 low.

 

Sounds like you shift selector linkage needs adjustment or replacement. Does it only do this when you select low gear? IE no issues in OD or the other ranges?

 

Correct, it only appears to be an issue with Low. When I bump the shifter from 2 to L, the linkage cable doesn't seem to move at all... I am wondering if there is just an electronic contact in the shifter that tells the trans its in Low or if the linkage does indeed need to move to change it to hold in low?

 

I checked the manual and it seems to indicate the truck should hold in first gear regardless of the 4wd setting. I hope so because I don't have the stock transfer case or any of the related electronics.

 

My 07 2wd autosauto in 1st when I select that gear.

 

I think it’s simpler than that. If you’re just not going into gear at the knob, it’s probably the mechanical selector. The ‘movement’ is under the truck, you won’t see much cable movement in the column. This guy just oils the crap out of his.
https://youtu.be/_J78a7rWiIk

I might just start doing this regularly as maintenance

 

AFAIK, The gear selection is electronically operated.
It gets input from the Park Neutral Safety Switch.
The rod under truck doesn’t move when going between D->4, or 2->L.
I should move from
P->R
R->D/4
D->3
3->2/L

The light should for the gear indicator should never go out completely.

I honestly can’t remember if my truck holds Low.
Only time I can remember needing to hold Low is Off-Road.
An then I’m in 4WD, and sometimes 4Lo

Maybe @gearcruncher or @Muddinfun will know.

 

Thanks all. I will lube the linkage below the cab just in case.
I agree with TNShooter, it seems like there is an electronic sensor. Maybe it is internal to the shifter, I see some wires in the shifter.

 

If it is indicating the incorrect gear or not indicating at all I would look at the Park Neutral Safety Switch and its harness.

 

The park neutral safety switch is on the passenger side of the transmission.

 

May good luck be with you.
The nut on the switch has a tendency to corrode.
It can be a bear to get off.

 

I will look at that. Right now it is indicating all of the gears properly with exception of Low, which it is showing as 2nd. BUT, in the recent past it will occasionally not indicate any gear and therefore defaults to D when I am driving (at least not defaulting to P, N or R )

 

Get scanned for a pending check engine code...

P0705 - Transmission Range Sensor Circuit Malfunction (PRNDL Input)

Either of the following conditions is met:
(a) Any 2 or more of the following signals are ON simultaneously. (2-trip detection logic)
•Park/neutral position switch input signal is ON
•R input signal is ON
•D input signal is ON
•2 input signal is ON

(b) Any 2 or more of the following signals are ON simultaneously. (2-trip detection logic)
•Park/neutral position switch input signal is ON
•R input signal is ON
•3 input signal is ON
•L input signal is ON


P0850- Park / Neutral Switch Input Circuit

Park/neutral position switch remains ON (P, N position) while driving under conditions (a) and (b) for 15 seconds. (2-trip detection logic)
(a) Vehicle speed: 43.5 mph (70 km/h) or more
(b) Engine speed: 1,500 to 2,500 rpm

Causes:

•Open or short in park/neutral position switch circuit
•Park/neutral position switch
•ECM

MONITOR DESCRIPTION:

These DTCs indicate a problem with the park/neutral position switch and the wire harness in the park/neutral position switch circuit.For security, the park/neutral position switch detects the shift lever position so that the engine can be started only when the vehicle is in the P or N shift position.When the park/neutral position switch sends more than one signal at a time from switch positions P, R, N or D, the ECM interprets this as a fault in the switch. The ECM turns on the MIL and store a DTC.

 

I have a cheapo scan tool. No codes thrown. Maybe I need to check using a better scanner.

 

You do need one that will read pending codes.
But if it is indicating as you said it will eventually post a CEL Code.

 

Follow the shift cable to where it connects to the transmission. On the other side is a switch. Get your favorite penetrating lube hehe and spray that switch on both sides. It doesn't sit tight to the transmission so you get both sides.

 

Sprayed everything no luck.

I think its the shifter. I removed the shifter cable but left the shifter plugged in. From 4 to D, there is no shifter cable movement, but by moving the shift lever side to side it is changing the gear selection from 4 to D. This should be the same scenario from 2 to L only no such luck, moving the shifter from side to side the gear stays in 2. I ordered a junk yard shifter from Ebay... we'll see on Friday.

 

If I'm not mistaken, all those lights on the dash get their signal from the ECU based on that switch. The shift is just a gate. It could be a straight line, doesn't matter. The only electric on the shift is the light bulb for the selector.

My shift had gotten really stiff going through the gears a couple of times. Last time it affected the lights on the dash. Soaked it good and worked it through the gates back and forth and it hasn't been an issue since

 

Update:
Installed the junkyard shifter today and it works! Placing the shifter in low both indicates low on the dash and the truck holds in 1st gear. There is apparently a sensor in the shifter that senses the side movement on the shifter (same as 4 to D) amd tells the computer to go to low. Thanks all for the advice!