My 1973 K10 Chevy Cheyenne
- Thread starter Chris
- Start date
Chris, did you expect all this work when you bought it? I know the tranny change was probably thought about. But, the frame welding, adding new gas tanks etc? I know Streetsides classics is never cheap, did they alert you to any of the issues?
It was on consignment so I haggled with them a lot on the price.
I wasn’t expecting the frame or gas tank work, that one caught me completely off guard. I guess it’s my own fault for not finding someone to check it out locally. I guess the good news is that it’s not rusted at all, thank goodness!
The transmission thing is just a want, not a need. I really like driving manuals better and this truck would be a whole lot of fun with a manual.
The time has come to re-wire my dual saddle fuel tanks on my 1973 K10.
I went ahead and purchased the Pollack valve from the newer (EFI model) K10s. It came with the Pollack valve, a DPDT switch, and this wiring diagram:
This wiring diagram makes complete sense to me. Where I am struggling now is I want to include a fuel pump relay in order to take the load of the DPDT circuit.
I'm using this relay:
https://www.amazon.com/dp/B07DY4MQKB?tag=wranglerorg-20
As I understand it, the relay should be wired as such:
Makes perfect sense thus far.
The part where I get confused is how this relay integrates to the original wiring diagram.
In the original diagram that came with the Pollack valve, the DPDT switch has 4 wires going to it.
1) Ground
2) 12V
3) Main fuel pump
4) Auxiliary fuel pump
Do those wires going to the DPDT remain unchanged with the addition of the relay? Given that the relay now feeding the two fuel pumps directly, I would imagine that the DPDT now only has a ground and 12V wire going to it, but then that has me confused about how it's able to discern between the main pump and the auxiliary pump.
I'm sure I'm overthinking this but since I'm not an electrical guy I want to make sure I get it right the first time.
I went ahead and purchased the Pollack valve from the newer (EFI model) K10s. It came with the Pollack valve, a DPDT switch, and this wiring diagram:
This wiring diagram makes complete sense to me. Where I am struggling now is I want to include a fuel pump relay in order to take the load of the DPDT circuit.
I'm using this relay:
https://www.amazon.com/dp/B07DY4MQKB?tag=wranglerorg-20
As I understand it, the relay should be wired as such:
| 1. Battery +12 V → 10 A fuse → Relay Pin 30 V | |
| 2. Relay Pin 86 (coil trigger) → should get switched 12 V from the DPDT switch, not constant power. | |
| • The DPDT switch position determines whether the relay coil energizes. • That's how the relay "chooses" between 87 (Main pump) and 87a (Aux pump). | |
| 3. Relay Pin 85 → chassis ground. | |
| 4. Relay Pin 87 → Main pump positive feed. | |
| 5. Relay Pin 87a → Aux pump positive feed. | |
| 6. Both pumps ground directly to |
Makes perfect sense thus far.
The part where I get confused is how this relay integrates to the original wiring diagram.
In the original diagram that came with the Pollack valve, the DPDT switch has 4 wires going to it.
1) Ground
2) 12V
3) Main fuel pump
4) Auxiliary fuel pump
Do those wires going to the DPDT remain unchanged with the addition of the relay? Given that the relay now feeding the two fuel pumps directly, I would imagine that the DPDT now only has a ground and 12V wire going to it, but then that has me confused about how it's able to discern between the main pump and the auxiliary pump.
I'm sure I'm overthinking this but since I'm not an electrical guy I want to make sure I get it right the first time.
Without wiring diagrams for the specific parts I'd say that makes sense. One pump powered by each relay state.
How are you switching the fuel level ground signal from tank to tank? Shouldn't that be part of the tank selector switch?
How are you switching the fuel level ground signal from tank to tank? Shouldn't that be part of the tank selector switch?
If you look at that diagram I posted for the Pollack valve, each tank gets its sender wire sent to a terminal on the pollack valve harness, then that same harness has a shared terminal that runs a wire directly to the gauge cluster. That way whichever tank is active will get its signal sent to the fuel gauge.
Installing the Dakota Digital VHX dash proved to be very simple. It works now and while I haven't installed it back in the dash, I have confirmed that all the functions work on it. It's nice having turn signal indicators, bright indicators, etc., all on the gauges themselves. The gauges also light up very nicely which will make driving at night easier.
I must say, ChatGPT is incredibly helpful when doing wiring. I was able to get almost all the wiring done today. I routed the pump feed wire on the Holley Sniper to pin 30 on my new fuel pump relay (controlled by the DPDT switch). Now when the Sniper comes on it will send power to whichever pump I have selected with the DPDT switch.
I'm very happy that this is getting fixed the right way.
My only gripe once this is all said and done is the wiring. I really want to clean up inside the engine bay / behind the dash. Not sure how to accomplish that but I need to find a better way to route wiring (I wonder if there is a way to hide it?) and I'll probably consider the Painless Performance harness so I can redo the entire vehicle with modern wiring and a modern fusebox.
I've been cleaning up this big mess under the dash the previous owner left. Fortunately it's nothing sketch, just sloppy wiring.
I got some strong magnets that I mounted to the bolt holes on the Dakota Digital computer. That way I don't have to drill holes to mount it, I can just stick it behind the dash with some super strong magnets.
Doesn't look like much but I can tell from turning it on it's a huge upgrade. The stock gauge cluster is poorly lit and hard to make out clearly at night.
I must say, ChatGPT is incredibly helpful when doing wiring. I was able to get almost all the wiring done today. I routed the pump feed wire on the Holley Sniper to pin 30 on my new fuel pump relay (controlled by the DPDT switch). Now when the Sniper comes on it will send power to whichever pump I have selected with the DPDT switch.
I'm very happy that this is getting fixed the right way.
My only gripe once this is all said and done is the wiring. I really want to clean up inside the engine bay / behind the dash. Not sure how to accomplish that but I need to find a better way to route wiring (I wonder if there is a way to hide it?) and I'll probably consider the Painless Performance harness so I can redo the entire vehicle with modern wiring and a modern fusebox.
I've been cleaning up this big mess under the dash the previous owner left. Fortunately it's nothing sketch, just sloppy wiring.
I got some strong magnets that I mounted to the bolt holes on the Dakota Digital computer. That way I don't have to drill holes to mount it, I can just stick it behind the dash with some super strong magnets.
Doesn't look like much but I can tell from turning it on it's a huge upgrade. The stock gauge cluster is poorly lit and hard to make out clearly at night.
For the factory lighting , the rheostat for the dimmer was on the light switch , wonder if it was just turned down?
Nice gauges ! Could the Magnets create interference with anything in the control module ?
I turned the dimmer all the way up and it still sucks. Modern gauges are backlit, these old gauges aren't. That means the numbers and needles don't light up on their own which makes it harder to see at night.
I didn't mount the magnets on the back of the control module exactly. I mounted them in the holes where the mounting screws are supposed to go through. I guess I need to ask ChatGPT if that could cause any issues. I didn't think it would but maybe I'm wrong.
That looks good. When you said dakota digital i was afraid it would be some gaudy thing with way too many digital displays and bright lights
I'm leaning more towards the Tremec TR-4050 HD transmission now. I found a company that sells swaps and the price they quoted me for the entire swap is actually not that bad. It's a brand new transmission and from the research I've been doing the TR-4050 is more "modern" in the way it shifts and it also handles a lot more power. Parts are more easily available and this "swap kit" comes with every nut, bolt, and adapter I need, even the pedal assembly and hydraulic kit.
Anyone ever driven a vehicle with a Tremec TR-4050?
Anyone ever driven a vehicle with a Tremec TR-4050?
I believe these TR-4050 are relatively new , as in a couple of years . I wonder how much real track record they have.
A quick google shows them being around since the 1990's
"The TREMEC TR-4050 is a 5-speed manual transmission for heavy-duty and off-road trucks that has been in production since the early 1990s, though it was not initially sold in the U.S. market. While initially used in other parts of the world like South America, it has since become available in the U.S. for both 4x4 and 2WD applications, often used to modernize older trucks. Its history is marked by its robust design, high-strength components, and versatility, making it a popular upgrade for classic trucks and other heavy-duty builds."
Interesting , I wonder why no real North America influx , given a 30 year history ?
Not entirely sure, but from the research I've done it appears to be a very stout transmission. It's rated for higher HP / torque specs and people praise the "modern" shifting feel. They also say it's a lot easier to get parts for.
I've owned several high performance vehicles with Tremec transmissions but never a truck. Then again, you don't see many trucks with manual transmissions anyways.
I remember always driving my step-father's early model Toyota Tundra with the 5-speed manual. I really enjoyed driving it because of the transmission. There's something about driving a truck with a manual, I must say.
All 7 of the trucks I've owned were manuals , I enjoy them .
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