A518 Lost 4th Gear

[MRickard]

Wondering if anyone knows if this is something simple. Checked fluid, wires, connections, and dash switch - all seem okay. I am wondering if it has to do with the lockout controlled by the dash switch or the 270 degree inhibiter deal. Anyone know of where I can see a wire diagram of the above mentioned circuits, and some specs as to voltages/resistance some of the sensors have, and if there is a way to bypass it to see if that is the problem. I do not need that 270 switch and do not mind bypassing it, especially if it causes things like this to happen. As always, just one more thing to go wrong. Everything else w/ trans been okay, and this just started. Is there a hidden fuse or anything?



--Thanks

 

[dpuckett]

We need more info as to symptoms and when and what it is doing. My bet without any other information is the TPS. That useless POS on top of the pump that controls the OD in and out, most times at some whim all its own. It is the reason I sold the auto I had. Mom has put in 3 or 4 of the danged things, and I've cleaned 3 of them. But, what exactly is it doing? Will it not go into OD at all? Or does it hunt around and drop into 3rd for no apparent reason? I still say TPS. $140 At O'Reilleys.



Daniel

 

[MRickard]

It acts like there is not 4th gear. Shifts 1-2, 2-3 are just the same as before, just no 3-4 shift. Everything seems fine, it just forgot it has another gear.

 

[CDegner]

Originally posted by dpuckett

$140 At O'Reilleys.

~$125 at Cummins or $108 (4 available) at Reliable goods.com Cummisn will tell you it is not their part. ASk them for part # 3621094.



Carl

 

[MRickard]

Okay I am stupid. Well I think you nailed that one... . I remembered adjusting the idle a few days ago, and just went out and checked it. Sure enough, it was disconnected and all tucked up and out of the way so I could adjust the idle. I plugged it back in



I will try it out next time I need to use it. I am cheap enough that cannot justify a cold start just to see if the O/D works, especially with these fuel prices. I bet that is what it is though. I'll have to check in on that deal and study up on it. Now that I think about it, seems strange how everything else seemed the same.



Atleast I have nice and clean wire connections for the inhibit switchs now!

 

[dpuckett]

When all else fails, look at the simple stuff. Duh!! Seriously, dont feel bad. If I had a dime for every time I did something like that, I'b be on a financial par with Bill Gates. IT's part of doing your own work, you miss little stuff or booger it up.



BTW- how do you define a cold start? I thought everywhere in the lower 48 had at least spring (60*+ days), if not summer (60**+ nights, 85 days). THough I dont blame you for not wanting to waste fuel to see if it works again. You have high enough gear to run all day at 65 in 3rd, though you may not have that much money.



-DP

 

[MRickard]

BTW- how do you define a cold start?

Heh heh - in this context, I was meaning a cold start as being the parts are all `cold' and such have excess tollerances and therefore excess wear. Also, makes more soot as to the incomplete combustion when cold, dirtying up my oil more. I know, too damn paranoid, and you are right - it <i>never</i> gets cold around here... . they give a big ``freeze warning" if it gets below 32 here... heh heh.

You have high enough gear to run all day at 65 in 3rd

I could only make it to about 55 (around 2000 rpm) - my truck totally does not like rpms above 2000, has a noticable more vibration/noise, and it will pull still for a few more rpms, but my power curve totally plumits. I need to do some work to improve that as it kinda sucks. I am sure if I floored it I could go much faster than 55, but it feels and sounds like it is burning a gallon a minute past 2000 (and no power). If I am driving down the highway in OD, and take it off, I slow way down and no power. And when it upshifts the gears in mild throttle, gets a surge of acceleration rather than a big drop in rpm like a torqueless gasser.

 

[dpuckett]

You might want to start a new thread....

... ... about your pump issues. With my 4. 10s, I can go 68 in 4th, (direct) and it pulls pretty good to about 60. Yours should pull to about 2500 RPM before falling off. THat assumes stock RPMs, which I no longer have.

 

[MRickard]

Here is what it ``should" be, although mine is an auto. Mine is the powerpack. I am wondering if it is that way so it runs clean, as they say it still meets CARB requirments, which I guess is pretty good power if it does.

 

[dan brooks]

Originally posted by MRickard

... . I remembered adjusting the idle a few days ago, and just went out and checked it. Sure enough, it was disconnected and all tucked up and out of the way so I could adjust the idle. I plugged it back in

Did the same exact thing a few weeks ago - freaked me out, too, because I'd been having problems with it kicking in and out of OD on vacation. Plugging the TPS back in gave me my OD back, and cleaning and applying dielectric grease to all the related plugs took care of the rest.

 

[MRickard]

I am glad it was simple (seemed like it was) because my friend had his car's transmission go out, then his pickups transmission went out, and we were actually using my truck to pick up a transmission at the junk yard when I notice mine was acting up. I had just finnished 3 loads of 2 yards of stones (about 5400 lbs) I know that transmission will be the first ``to go" with this truck, but I baby it a little. I do a lot of mountain grades though ... .