2003 Burb C2500 Need More POWWA
 

Hey everybody, I am new. I am new to the forum, trucks, towing, rving.

I recently picked up a new 22' travel trailer and pulled it up to mammoth mountain in California. When i hit the grade, the green toad really showed us what shes made of.
Im pulling an estimated 4000lbs and only managed 35MPH while trying to keep the RPMS less then 6k(2nd). I almost had to stop to cool her off but we crested just in time WITH the heater on. 92f outside for those curious.
I have been lurking around here a few days, already ordered a bracket and new tru-cool 40k. I have seen people doing mild bolt-on micro upgrades to full on turbo monsters!
My goal is to get not only long life out of the toad but better performance for towing these hills. 3200ft - 8300ft. My truck has 150k miles and she runs great other then the lack luster performance, imo.

i'd love to know what you all recommend. I am a decent mechanic but usually dont delve into whole engine rebuilds or cams but dont mind paying for other peoples skills.

-Prinler

Gears. 4.56 or 4.88 depending on tire size

Followed by cam and long tubes. Factory intake and exhaust will outflow most of what youre trying to do

After that, youre basically gonna need boost

4000lbs and 35mph dont compute in my peesized brain. Youre draggin a lot more than you think I'd bet. My 5.3 Tahoe doesnt even bog that hard with 6500 behind her at 5000' above sea level

Edit: I would also suggest 91-93 octane and a related tune. She is probably running in some KR already, and when she gets loaded and hot, it only gets worse. Advancing the timing (done with a tune only) and running Premium will make your life so much more enjoyable, especially when you have to put your foot in it

Definitely on the right track with the trans cooler.

I also agree with 4.56-4.88 gears and a good tune.

4k is hardly anything my 4.8 (when stock) pulled nearly double that and never needed more than 3500rpm through the Black hills of South Dakota. Something might be off with your weight calculations.

Id love to boost it, sadly i live in California. I doubt they would let that fly.
I have been trying to find the details of the grade between bishop and mammoth but I can not. I know its pretty darn steep and long. Like i mentioned 4k ft climb in not that many miles.
All this talk of Tunes? I live in the middle of "BFE". Does this mean i have to take it to someone, buy something?

I think im gonna hook up the TT and take it to the weight station and get as ticket this weekend. Then we can talk real numbers.

You mentioned not needing more then 3500rpm, my option to go faster then 35 was 2nd gear and it was screaming at like 5k. I really didnt like that and the heat was creeping up fast. Could something be wrong with the truck?

Check and make sure your cats aren't clogged

make sure the air filter is clean

make sure the MAF is clean

tune is best done by a shop or a person with lots of experience. May have to shop around or find a mail order place. I would avoid blackbear for mail order tuning

as for the climb, I've been up Raton Pass, which is 6-7% for a majority of it, and needed 3rd, but the speed limit is 55 through there, so 2nd might have been better. I was pulling ~3300lbs at the time. I have a full bolt on and cam'd 5.3. She puts to the wheels what a tune only LQ9 does, so essentially I have the same power you do: maybe 40-50lbs less torque tho. You have an LQ4, but just work with me on the bench racing lol

I have 4.10s with 33" tires. I actually want more gear and eventually would like to step up to 35", but different discussion for a different day

give your ol girl a look over, make sure she can breathe ok. Get a scanner so you can keep an eye on real time temps and it may be time to look at cats and o2 replacements depending on how she's been driven. Driven harder generally means the cats are cleaner. I don't know how you can inspect them without dropping the Y pipe, and if you're doing that, may as well just replace them. I am not a fan of aftermarket cats at all. I'd look for OE replacements, maybe on a factory Y pipe. I don't know where you should look for those. Brand name exhaust companies will offer stuff, but may not be the same quality as OE

6k at 35mph should be 1st gear

706/862 heads and a small cam will make a huge difference. Just might have to run 91 octane, though...might.

Let's Talk Torque: LS Truck Upgrades - CPG Nation

Gears will surely help. Getting a tune will also help. You don't have to go to a shop, you can do a mail order tune with someone like atomic performance

One thing worth looking into is the radiator and the fan clutch. Has it ever been replaced that you know of in the 150K?

If not, you might find the cooling stack is slightly plugged up. The diesel guys run into this alot. All the road debris builds up and the cooling stack loses its efficiency. Same with the fan clutch, Over time it wears down and becomes less efficient. They often find out when it's too late and overheat on long heavy hauls.

You may want to consider doing all the cooling Items.