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A cheap chinese brand (Topoint). But my research indicated that the cheap sensors usually work OK initially but but don't last as the OEM sensors. Since I was doing this by trial and error I didn't want to spend a bunch of money on something that may not be the problem (I've already done that a lot). It is unlikely that I would get 4 new sensors that have the exact same problems as the 4 sensors that that I'm replacing. I still have the original sensors that I could test and reinstall if it would help for troubleshooting.

So I think I can rule out clogged cats. I got a cheap chinese backpressure gauge. The only time the needle would move off the peg is when I'd rev the engine and then it only bounced and went back on the peg. It stayed on the peg at idle, steady 4K RPM, and floored in gear at 2K RPM. While the gauge isn't very accurate I checked it against a couple of tire gages. It appears the first line is about 3 psi and it never got there (other then bouncing a little when revving the engine). So the exhaust pressure doesn't ever seem to exceed 3 psi. So any recommendations on what to monitor if I take it for another drive? O2 sensors on both banks, manifold pressure, fuel trims? Anything else? Edit: I guess it would be good to monitor timing advance to see if it is pulling timing.

If I add 21 to 24 I get 45" which is closer to the 44" I measured but a lot taller than the 40.8" per the 2024 Chevrolet camper loading guide. Edit: I went and carefully measured again. I get 44.5" so the Chevrolet Truck-Camper Loading document is definitely incorrect. It looks like they never updated the cab height dimension when they changed the body style.

The the bed floor to the top of the rail can't be 14", I would have noticed if the rails were that low (but I didn't measure them). The measurements I've seen are 22.4". And if I add 22.4 to 24 I get 46.4" which is even higher than the 44" I measured. I think there is something screwy going on with GM's dimensions.

I went by a Chevrolet dealer to take some measurements. Interestingly I measured 100.5" from the front inside of the bed to the "nub" above the tail light which is exactly the same as my camper length in that area. So I'd probably need a small spacer to ensure some clearance. What concerns me is the measurement I wrote down for the height from the bed to the top of the cab is 44" (not including the shark fin antenna). I've been using 40.8" (dimension E = Top of bed floor to top of Cab per attached document). Did I write down the wrong number or is it really 44" to the top of the cab? Silverado & Sierra Truck Camper Loading (dimensions).pdf

Deleted - Accidentally responded to message.

Thanks! So it looks like that bump would be a built in spacer for me and that I'll have enough clearance for the exhaust and septic with 105" to the back of the bumper. It sounds like I'll also clear the tail lights.

Another thing I'm coming up against with the GM trucks is the longer bed length. I know I'm going to have to raise my camper a couple of inches to clear the bed rails. Once I do that it looks like I'll have plenty of clearance for the cabover portion of my camper even with the truck's shark fin antenna. The Ram trucks have a higher cab and I'd probably have to relocate the shark fin antenna unless I want to raise the camper even higher to clear it. I'm not even considering Fords because I'd have to use 4x6s. However, the longer bed on the GM trucks might make me have to move the camper back so my generator exhaust can clear the bumper. The distance from the front of the camper to the generator exhaust is 106.5". The dimensions I'm seeing for GM long bed trucks is the distance from the front inside of the bed to the back of the bumper is about 109". Does anyone have an actual measurement of the distance from the front inside of the bed to the back of the rear bumper? Edit: Assuming the new long bed is 2" longer than my current K3500 8' bed it looks like I'll also have problems clearing the septic drain on the other side and the tail lights unless I put a 1.5" spacer between the camper and front of the bed. Thanks

I will be using the truck both to haul my camper and to haul things around town and on my property (firewood, etc). The camper will go on and of several times a year. On my current truck (K3500) I can remove and reinstall the tailgate myself without tools and there are no wires to deal with. Since I'm unlikely to find a gas long bed crew cab dually that will suit my needs I'm considering custom ordering a truck. When I select the options I want on a LTZ I'm forced into a powered tailgate. I have the option of upgrading to a Multi-Flex tailgate (which is still a powered tailgate) for around $250. If there was an option for a lightweight tailgate without wires and didn't need tools to remove I'd select that. But once I'm forced into the powered tailgate I figure I might as well select the Multi-Flex tailgate if it doesn't add much more weight. Edit: Now that I've re-read the option is says the MultiFlex tailgate has Power Lock and Release. And if I add it it removes Power Up and Down Tailgate. So the weight difference is probably small although I'd still prefer that it would let me option the truck without either and still get the other options I want.

It looks like I'd wind up the the powered tailgate since it is tied to some options I want. Once that happens it doesn't seem like the Multi-Flex tailgate would add much more weight over the powered tailgate so I might as well add it if I think I'd use it, does that sound correct?

I can monitor vacuum using Torque Pro. I checked at an idle and reving the engine and it didn't indicate a blocked exhaust. My brother-in-law (who is a mechanic and services rafting vehicles) thinks it is a clogged cat (he says he sees a lot of these) and suggested removing the upstream O2 sensors and driving around. I didn't like where the exhaust could impinge when doing this and decided to order an exhaust pressure gauge. I might try driving around with the upstream O2 sensors removed or I might try logging the intake manifold vacuum and the bank 2 sensors if the exhaust pressure gauge doesn't work out. Thanks for your input!

Yes, the engine keeps running with dump valve open. I'd expect the fuel pressure to drop at full throttle when the problem is happening if the fuel flow volume to the injectors is insufficient.

That makes sense and is sort of what it feels like. But since the fuel pressure stays around 58 psi when the problem is happening it would mean that the fuel pump, fuel filter, and regulator is doing their job and mean that it is the injectors (more than one) if it is a fuel problem, wouldn't it? Would plugged cats cause low voltage on the O2 sensors? I could do another run monitoring bank 2 O2 sensors and whatever else you think would be helpful.

I got a hose extension for my fuel pressure gauge and drove around with my fuel pressure gauge taped to my windshield. I got the truck to act up and the fuel pressure was still around 58 psi when it was losing power and the check engine light came on (P0300, P0137, and P0157). I logged fuel trim and Bank 1 O2 sensor values in Torque (I screwed up and didn't log bank 2 O2 sensors) and attached the file. I don't know enough to know what the data should look like. If anyone wants to take a look it would be appreciated. I've ordered an exhaust pressure gauge and will check for a clogged catalytic converter next. trackLog-2024-Sep-04_13-14-19.ods

I have purchased custom order cars before from high volume dealers that provide substantial discounts. Right now I can custom order a Ram for about 4% less than invoice plus any factory incentives available at the time. Are there any similar dealers for GMC and Chevrolet trucks? Preferably in northern California.

I did a side to side comparison in both the option tab and the summary tab and couldn't figure it out (you get cross-eyed after a while). There was a discount for the All Star edition in 2024 but not in 2025. There is still a discount for the Texas edition in 2025 but I can't get that in California.

I'm building 2025 Silverado 3500 on the website. It appears that the All Star package is just a combination of the Safety and Convenience packages but it costs $245 more. Is there something more in the All Star package than comes with the Safety and Convenience packages?

It's interesting that the F60 and VYU options don't increase the FGAWR on the crew cab DRW diesels but appear to be available for them. Must bump up against another limiting factor.

Thanks, It says that the 4WD gas FGAWR is 5200 lbs but it doesn't state that the F60 heavy duty front spring/camper package increases FGAWR. It also states that it isn't available with the VYU snow plow prep/camper package. It does state that the VYU snow plow prep/camper package package increases FGAWR but I can't find where it says by how much. Are the front springs different between the F60 and VYU packages? Does the F60 spring package increase FGAWR? If so, by how much?

You bring up an interesting point that I may not need (or want) the camper springs on my truck, especially on a gas crew cab long bed truck. My camper weighs about 3500 lbs completely empty/dry. I figure I could add as much as another ~1000 lbs completely packed with all tanks full but most of that weight will be centered not much forward of the rear axle. And then perhaps another 1000 lbs scattered throughout the truck for people, camping equipment, pets, etc. And then perhaps another 500 lbs tongue weight for a boat I may occasionally tow. So most of the weight will be centered closer to the rear of the vehicle than the front. An exception could be the ebikes that I currently put on a hitch rack in the front of the truck. One advantage of the camper springs would be to reduce squat when braking but that really isn't a problem with my curent truck. I was always focused on not exceeding rear GAWR on my current crew cab long bed SRW and didn't pay much attention to the front GAWR, especially since the rear squats much more (without the air bags filled) than the front when loaded. I looked through my old weight records but couldn't find where I actually recorded the front axle weight. I can't find the front GAWR for a 3500 Silverado/Sierra but the Ram is 5500 lbs (6000 lbs with diesel) and I'd assume the Silverado/Sierra is similar. I don't see myself exceeding that.

It I custom order a build I will include the heavy duty front camper springs. If I buy one off the lot I'll make sure it has the springs or snow plow prep; or include the cost of changing the front springs in my evaluation. I wish there was an option for rear anti-sway bar, I'd include it if it was available. One advantage Ram has is the auto leveling system. I currently have a SRW but am tired of having to pay attention of what I'm loading and leaving stuff behind. I don't want a DRW but am going to one because I need it.

I'm considering purchasing a new Silverado/Sierra 3500 long bed DRW to haul my truck camper and have some questions (I'm also considering Ram trucks) and have some questions. About half the time the truck will be used without the camper on so it will be removed several times a year. A lot of the trucks have the Multi-Flex tailgate but I'm concerned about how much it weighs (it looks heavy). On my K3500 I can just unhook the cables, open the tailgate about 30 degrees, and lift the tailgate off. However on the new trucks it looks like I will need a wrench to remove the cables, get underneath to disconnect the wires (I guess the connector is above the spare tire), and then lift it off similarly to my K3500. How much does the Multi-Flex tailgate weigh? And how much does the power up-down tailgate weigh? Is it practical to be removed and reinstalled by one person? Is there an extension available for the wiring harness to make it easier to get at and a weather plug? Will the computer throw codes without the tailgate? What tech features will be disabled when the tailgate is removed and a large camper is on the truck? The camper is 8 feet wide and will overhang the cab and rear tail lights. Will blind spot monitoring, surround view, etc. still work? How about if I mount a OEM backup camera on the camper? I also have a question about double cab vs crew cab. Is the back seat and everything else the same in the double cab as it is in the crew cab and just some leg room is lost or is it smaller? The Chevrolet build site says some options only come with the crew cab, is that true and they don't come with the double cab oris that just poor wording? Thanks

Here's my results: Fuel pump running (ignition on) and engine off: 58 psi for a couple of seconds and then drops to 50 psi when the pump stops. The pressure slowly increases to about 55 psi over about 5 minutes (nothing running). I'm assuming this is because of heat soak. Fuel pump running and engine idling: 50 psi. When I press the relief button on the gauge the dial drops to zero but no change in engine idle. I suspect there isn't much flow rate through the gauge connection on the fuel port. I only got about a cup in about 30 seconds. Also, I have an electronic version of the service manual for my truck and I couldn't find a fuel pump flow rate specification anywhere.

By dump valve I assume you mean the push button pressure relief valve on my fuel gauge. It has a hose on the valve so I could route it to a container and press the button while the engine is running. Any idea what kind of flow rate I should expect through that valve with the engine idling? Thanks Edit: I found a rating for 65 GPH (about 1 GPM) online. Does that seem reasonable? It didn't state the pressure at that flow rate.

2000 K3500 7.4L I've been having this problem for years now. When the truck is under a load for a while (like when hauling my cabover camper up a grade) the check engine light will come on and the truck will lose power. It will also not downshift as easily as it normally does. I can sometimes feel it happen before the light comes on, almost like a switch is thrown. Sometimes I can let off the throttle and stomp on the pedal to get some power back for a while. Initially I would pull the codes and the only thing present was P0300 Random/Multiple Cylinder Misfire Detected. If I clear the code it will initially have more power until I go up a grade again. The temperature gage is usually right in the middle to a little above middle and no signs of overheating. I had also checked my fuel pressure (but not while driving) and it was within specification. Now the P0300 code is accompanied with pending low voltage codes for all 4 O2 sensors (P0131, P0137, P0151, and P0157). Things I have replaced: All 4 O2 sensors Distributor, (including cap and rotor) Spark plug wires Spark plugs Engine Fuel filter (about 8K miles ago) I haven't replaced the ignition coil. I know the fuel pressure regulator leaks because the engine will crank for a while before it starts after it has sat for a bit but not cooled down. It starts fine when cold and when hot if restarted soon after it is turned off. I guess the next things I'm considering is a bad MAF. I considered a plugged exhaust but that doesn't make much sense since it will initially run good and then abruptly loose power although it does "feel" like restricted exhaust or lean mixture when it happens. I have a OBDLink MX+, Torque Pro, and OBDLink. What should I monitor during driving to help narrow this down (I'm getting tired of troubleshooting by replacing parts)? Anything I can test for? Edit I took the MAF off and didn't see anything obvious. No debris and not oily. I also did the test where you check to see if the flow rate doubles each time the RPM doubles and it did (I didn't go over 4K RPM). I also checked the throttle position with the engine off but ignition on. 0% at no throttle and 100% when floored. There is an option for fuel pressure in Torque Pro (which interestingly disappears once connected to the OBD2 reader) but it always stays at zero. But fuel flow rate is available. From what I have researched the low O2 voltage indicates a lean (vs rich) mixture. I guess the next step is to see if I can reproduce the problem while monitoring my Long Term Fuel Trims to see what they do. I'd drive around with my fuel pressure gauge taped to the windshield but my hose isn't long enough.