Last week I needed to pull my 2500-3500 (guesstimate) pound 18 ft dovetail trailer up a pretty steep road (1/2 mile driveway)
The drive is right around 30% grade. I tried going up it in drive with OD off and it would not make it! I even stopped and gassed it again but she pretty much just sat there. I had to put it in first gear then it went without problem. Does this sound like things are working properly? I don’t understand this, if I am in drive should it not go into first automatically? This tranny always shifts great but the TC shudders if I feather the throttle while its locking up.

 

Search up on the TC Shudder thing. I have done a Search on "line Pressure" and found lots of adjustmens that help out in the Shifting and shuddering of the TC.

Sounds like the TPS may need adjusting or some internal pressure adjustments.

https://www.dieseltruckresource.com/...threadid=37559

 

Hmm, read your own Sig Dusty! "THE TC HATES THE 370'S" LOL. It is probably what Lil Dog says, prolly need some presure.

Dom

 

Hey Lil-Dog, Deezle 1
Thanks for the response.

1. The TPS is functioning correctly (at least per spec). I did however bump the voltage from a start of .8 volts to 1.02 without any noticeable changes.

2. TC: The TC is what it is, a real pile. I have swapped the trans fluid out and verified the TV cable adjustment, even put a shift kit in the VB. The TC is just inefficient, the fluid coupling might as well be air.

I am trying to understand why, when in drive, it would not go up the hill. But in manual first it did. Maybe it did not shift into first gear automatically. As far as I can tell I never do 2nd gear starts when on level ground. But heck I could be wrong.

 

Sounds like a pressure govener whatchamacalit thing. I had it pile in my trans twice. Apparently the shift into low is based on line pressure. My trans would do that same thing, want to start in second so I would manually shift it into low and bingo. Both times pan was dropped and pressure govener whatchamacalit thing replaced and all ok.

 

Re readin again, sounds like what he said above. A leakin seal or bad servo or somethin bad.

Can't remember exactly but manual low overides pcm-to an extent. Fluid will be directed to the 1st gear clutch pack automaticly....sound right???

on edit:Pretty much beat me to it......

 

Apart from being kinda sad it was kinda funny at the same time. I was basically sitting there gunning it (not beating it) and she just kinda sat there like a lump . Thought to my self "self" you arent moving, either go up, or back the dang thing down the drive. So I searched for options and before I went to the depths of 4LO I tried 1st manual and off we went.

 

I bet you can fry hotdogs on that stock torque convertor sometimes. What will it stall with the fuel you have? Probably up to defuel. Great piece of crap these tq convertor are. I think a wash machine transfers more torque than these convertors!

 

I have never done a stall test on it, the truck has lots of power, its just really frustrating knowing what this thing is capable of and not being able to use it. Hit to go pedal and you know you expect to go somewhere and yep its zoom zoom and not really any significant go. This is my first auto in a truck and probably my last. I will someday cough up the bucks for at least a TC. Funny thing is the previous owners already had the trans replaced, and the truck has under 100k.

 

The 3k GSK seems to have made my tranny like 3rd gear a lot. When you arec oming to a stop sign or something, but dont completley stop, the tranny will stay in 3rd gear instead of dropping to 2nd or first. It used to not hesitate to drop a gear, but now it likes to stay in 3rd. I usually have to give it a pretty good amount of throttle to get it to down gear out of 3rd if im going ver fast. It does ALWAYS start in 1st gear though. It never tries to take off in 2nd or 3rd as long as i have stopped, or almost stopped before i take off. I need to adjust my TPS and see if i can get it where it downshifts better. It used to hang upshifts, and was pretty slow unless i used the lockup switch before the GSK, but now it NEVER hangs an upshift at WOT, and I can acutally pass someone now without locking the converter . My converter hates the power right now. It not only shudders, but it slips pretty bad if i mash it in overdrive anywhere under probably 1800-2k rpm's, but im planning on a new torque converter VERY soon, and i cant wait to get one in. It should be a different truck

Eric

 

When you shift into manual low, the transmission is designed to boost mainline pressure, because it knows you want to do some work. The extra pressure would help to eliminate slippage, whether in a clutch or TC. In addition, manual low applies the low/reverse band to help out the low roller clutch. The band is not applied when in drive/1st gear.

 

Torquefan:
Sounds like a good explanation to me. I understand the fundamentals of an auto but not all of the workings. Is it ever advisable to manually shift an auto like in a race situation. From your explanation it should have a better fluid connection, less fluid shear maybe ?

Cumminsdriver635: Hear ya on the 3K GSK what a great improvement. Maybe the trans didnt shift into first, come to think of it I just started up this hill probably in second by the time I got to the steep part and she just started slowing down

 

When loading an auto trans to its maximum, such as starting out with a heavy load uphill, I would shift manually to "help out" the transmission.