Gauges and tranny questions

[XOC]

Hey gals and guys ...

OBS 96-97 4x4 superduty reporting for questions:

1) how can i find out the electrical requirements of the various cabin gauges ... ( i iwant to replace them all with VDOs or something ) ... and yea, I'm talking about speedo and tach and oil and fuel and temp and whatever else already has sensors.....)

2) i have a slushy. I put it in reverse and impatiently stomp the gas to back up fast. Theres a loud vibration/clicking-sound and around 0 torque. I let off the throttle and apply it more gently and i am ok. ... this can't be the clutch slipping?

2a. could this be a this a side-effect of leaving the front hubs locked ( in 2wh mode, which the manual claims is fine except for gas economy)?

2b. another weird thing is parking facing down a hill, and then starting and having to back up onto level ground. Even though the rear wheels are on asphalt, the engine just revs and there is little more than slight jostling ...

but on the road even a hill i can stomp and it sure seems like it grips and flings itself forward, i dunno .... gaasaaaaaaa

Please school me & thanks.

Lee Of San Diego

 

[DaveBen]

1. They are standard guages, except for the speedo. That is driven off of the rear end sensor (speed sensor). I have Autometer guages and they were not anything special.
2. You may have a tranny going south.
2a. The only effect of locking the hubs in on pavement is binding of the front axle U-joints when turning. I leave my hubs locked for months at a time.
2b. See 2 above.

It is not good to refer to the throttle as "gas".

Dave

 

[XOC]

On the gauges I was wondering if there is a reference for the voltage range, polarity etc for the stock senders. Are they all just 1 standard spec?

Yea I am worried about the tranny. I didn't know if I could tell if it was a diff problem vs tranny vs ???

Thanks.

 

[MJ Synthetics]

On the gauges I was wondering if there is a reference for the voltage range, polarity etc for the stock senders. Are they all just 1 standard spec?

Yea I am worried about the tranny. I didn't know if I could tell if it was a diff problem vs tranny vs ???

Thanks.

When is the last time the tranny was serviced?

 

[DaveBen]

All of the guages are "standard spec" as to the sending units and voltages. One size fits all.

Dave

 

[XOC]

When is the last time the tranny was serviced?

Unknown. I bought it used a couple years ago, haven't put many miles on it since, and 0 towing miles. It shifts fine and accelerates fairly well if I floor it, but I have been suspicious also about how much friction there is in the drivetrain.

I've noticed on a fairly steep downhill, one where I know my car would accelerate if I was coasting, the truck barely maintains the same speed. I don't know if that's typical for trucks with larger mudder tires - not super swamps just Toyo A/Ts.

All of the guages are "standard spec" as to the sending units and voltages. One size fits all.

Dave

Ok cool, well that is good news, because the stock gauge cluster is not exactly high styling. Thanks.

 

[BJS]

I've noticed on a fairly steep downhill, one where I know my car would accelerate if I was coasting, the truck barely maintains the same speed. I don't know if that's typical for trucks with larger mudder tires - not super swamps just Toyo A/Ts.

This may be attributed to your tires but is also attributed to the fact that most cars unlock the torque converter when you get off the throttle. Depending on PCM code or chip programming the 94-97 trucks may or may not unlock the converter(earlier years unlocked converter, later years did not and is preferable for trans wear), if the converter is locked the engine serves as a reasonable brake for just the truck, several things contribute to this. When power is not needed from these engines fuel delivery is cut off completely so the engine begins to work 100% as an air pump and there is no little power stroke like in a gas motor to help in that rotation it all comes from the driveline. However you do not have an intake butterfly to restrict air intake which is what a gas motor uses for engine braking.

If you are concerned about the ability of the truck to coast and friction then toss the transmission in neutral and you should feel yourself picking up speed.

 

[XOC]

This may be attributed to your tires but is also attributed to the fact that most cars unlock the torque converter when you get off the throttle. Depending on PCM code or chip programming the 94-97 trucks may or may not unlock the converter(earlier years unlocked converter, later years did not and is preferable for trans wear), if the converter is locked the engine serves as a reasonable brake for just the truck, several things contribute to this. When power is not needed from these engines fuel delivery is cut off completely so the engine begins to work 100% as an air pump and there is no little power stroke like in a gas motor to help in that rotation it all comes from the driveline. However you do not have an intake butterfly to restrict air intake which is what a gas motor uses for engine braking.

If you are concerned about the ability of the truck to coast and friction then toss the transmission in neutral and you should feel yourself picking up speed.

Hmm interesting. Well, when I said my car would coast I did mean in gear, but what you explained helps a lot in understanding this as a possibly normal thing. The car is 5-speed, gas engine, and a 7k redline. The truck as you say has quite a few differences -- and the whole thing about it shutting off the gas I did not know, but now that you mention it, it explains a lot. I wonder if that's also why, when I am just coasting to a stop like at a red light, the engine sound disappears during the coast, but then picks up chugging once it's at idle. (I hear exhaust a lot better than most since I have stacks right behind the cab ... which is a single cab.) I will definitely have to do the experiment of putting it into N when I'm going downhill to catch the difference.

But so, is there any driving experiments I can do to tell if my problems are in the tranny vs the diff(s)? I know my front diff has a very slow leak, but this problem happens in 2wd mode. I haven't noticed any visible problem in the tranny or rear diff.

 

[XOC]

All of the guages are "standard spec" as to the sending units and voltages. One size fits all.

Dave

Is there any way you can link me to the specific gauges you installed? I am seeing all kinds of variations.

Like mechanical vs electronic, and for speedo there is a 3rd type "pilot tube". On fuel there are different ohm ranges (0-30, 0-90, 73-10), and so on.

 

[DaveBen]

I used the Sport Comp series of gauges, but that is my choice. There are many choices. Auto Meter is the site.

Dave