Another JR

There are multiple part numbers of rear spring packs. Remember that thread?

I wouldn’t say the ride was uncomfortable (for a 1 ton truck) with the stiffer springs, but the unloaded ride is noticeably stiffer with the the camper springs. I ordered my 2021 3500 cclb with the camper springs (not plow package) rated at 5600 FGAWR. The base springs would have given a 5200 lbs FGAWR. More important to me than the stiffer ride, the rebound response of the front suspension with the stiffer springs was faster than the rear suspension. This caused the front end to pitch up when going over dips at highway speed. It was worse with the camper on because my camper puts very little weight on the front. It might have been curable with different shocks, but I didn’t need the weight capacity and I wanted the softer ride. I bought the 5200 lb springs and swapped them in. The camper springs did make the truck stiffer in roll, which would be a benefit with a hard sided camper’s higher cg. I would suggest researching the weight and fore/aft cg of the camper you are buying, and then calculate the load added to the front axle by the camper. If it doesn’t add at least 300 lbs to the front axle weight I’d stick with the base springs. On the other hand, if you think you may wish you had bought them, go ahead and buy them. It only costs $600 plus labor to change them and it’s an easy job. I’d rather have the higher axle rating on the data plate with lower rated springs than vice versa.

I may be using the wrong terminology, but by “overloads” I meant the separate leaf spring above the main spring pack that engages its own set of bumpers on brackets bolted the frame. There was quite a bit of discussion about the 2500 not having this spring and not having the frame mounted bump stops for it. A person was wanting to add that spring and the bumpers to his 2500.

I bought mine with the front camper springs option. I ended up switching the front springs back to the base springs for my model because my camper only puts 100 lbs static weight on the front axle, and I didn’t like the pitch up effect of the front suspension response being stiffer than the rear. If you get into considering camper springs I can offer advice based on my experiences.

Single rear wheel or dually?

There are other recent threads on this, but here’s a summary as I remember it. The rear spring pack on the 3500 has one additional leaf. The 3500 rear spring system also has an overload spring where the 2500 does not. The 3500 GVWR and payload rating are higher (obviously). My 3500 cclb gas has a payload rating of 4,055 lbs. Typical 2500s have 3000 to 3400 I think - others may jump in with actual numbers. Because of the suspension difference, the 3500 has a bit stiffer ride at a given weight versus a 2500. The rear seat especially feels the stiffer ride when the truck is empty. With my 1800 lb slide-in camper in the bed the truck rides nicely. The 20 inch wheels on a Denali will make the ride even stiffer versus 18s. The rear tire pressure monitoring system alarm point is about 10 psi higher on the 3500, limiting how low you can set the rear tires for empty running to 63 psi without getting a warning. I wish I could go to about 55 when empty (I have 18 inch wheels). On the 2500 you can. If you have a diesel, I believe the 3500 has a slightly larger rear differential ring and pinion gear set 12” versus 11.5” on everything else. On the 3500 you can only have the huge moose antler towing mirrors. They seriously obscure the view to the right to see pedestrians at intersections. Make sure you drive trucks with both the standard and towing mirrors. This might be a big factor for you. On the 2500 the towing mirrors are optional. The 3500 has the much cooler “3500” emblem on the doors. However if you get the Denali there is no emblem so you constantly have to tell people it’s a 3500 if you want to be cool.

I think the OP is talking about a slide-in truck camper. I have a Four Wheel Campers pop up truck camper and I get about 15-15.5 mpg with the camper on and around 17.5 with it off when driving 65-70. It only weighs 1800 lbs. Of course, a tall, heavy non-pop-up camper will be a whole different story.

TRD Off Road Premium with KDSS in “Lunar Rock” color.

I just ordered/reserved a new 2023 4runner. I wanted the proven reliable drivetrain for mild overlanding and trailhead access for the next 20 years.

Part of the assembly that comes on top of the second battery in a gas truck is a battery isolator. Loads you connect to the aux battery are isolated from the starting battery when the truck isn’t running so they won’t deplete your starting battery. This is different from the diesel, which has the batteries directly connected at all times because they both are needed for starting.

The vent for the rear differential opens in the area of the fuel filler neck. The vents for the transmission, transfer case, and front differential all are routed to high points but I don’t know where. It would be good to know where they are and not spray there.

I was thinking more about design issues other than serious blowby that cause deposits due to condensation. Bad ring design, improper assembly, or badly worn rings that cause a lot of blowby can cause sludge, but does an engine of an otherwise good design that uses some oil due to poor break in practices tend to have major sludge issues? I don’t have direct experience with this to know, and I appreciate being edumacated.

The importance of break in procedures to ensure a good long term ring seal without destroying the honed cylinder surface, and the breaking in of the axle ring and pinion without causing damage that causes tooth surface spalling in the long run are one thing. The tendency of an engine design to collect sludge for various reasons is an entirely different issue.

Any idea why the LEDs aren’t lasting?

Hi Grumpy Bear. I was just reading what you had put in your post: “When GM designed the first SBC the rods were built to take 110% of designed load at 6K rpm for one million cycles. It was considered infinite life. But what does it mean?” In the next paragraph you then described the test load as 110% of yield, which seemed like a misinterpretation to me. Sorry if I read it wrong.