Advice needed guys!

[arneson]

Id bet it has to do with big tires and the gears. Imo anyway. Unless you regeared your truck. And i gauranttee once u have twins, u will never want a single again. The very best mod i did to my truck forsure, towing is unreal now. And i pull very heavy everyday. Once my motor is done, i will be going bigger twins, but for a stock motor s475 overstock cant be touched for towing again imo. Not to mention way more fun on street with twins at 600+hp then a single, least i sure think so. Way smoother power.

 

[workin' diesel]

Alittle off topic, but what line of work does one need to be in to afford such awsome upgrades???

 

[arneson]

Who and what upgrades are you talking?

 

[S Phinney]

All your info points more to tire size and gearing than anything else. With the combo you have you need to drive it a a little more like a gasser to keep egt's in check. That means speed up before the grades when possible and pull in the lower gear not fifth. Depending on the tuning specifically timing and lower to intermediate PW it cold possibly help some but now where near as much as changing driving habits.

 

[workin' diesel]

Probably anyone on this thread so far. Tranny's, compound turbos etc...

 

[arneson]

Gotcha, wasnt trying to come off and flaunt my mods. Just personal experiences. I do however take pride in my truck. I orderd this truck new, put every mod on it, and payed for everything myself. I own a landscaping company, have wife and 2 kids, and just built a house, i work for everything i have. Its takin me 6yrs to get to this point and have been talkin motor build for 2yrs now. Im getting close. This sportis isnt cheap as im sure u know. sorry for the de-rail op.

 

[S Phinney]

I ran a very similar setup before and towed heavier than the op but not so more on bigger grades. My opinion comes from what I noticed when towing myself. My main goal wasm to keep egt's under 1100 max and was able to stay under 1000 ninty nine percent of the time. I bust ass as a Masonry Contractor most of the time and a little Diesel work on the spare time. Put that together with a lot of luck and you get to see some of these luxuries in a few years.

 

[firefighter13]

Thanks guys for all the input!! It sounds like twins will be the answer! I tried all the tricks like speeding up before the hills and using momentum etc, but don't like getting too fast with a trailer that size behind.

I work in mining and have had this truck since it was almost 2 years old and it has been paid for for a long time now. I looked at buying a 2013 Duramax to replace it early this spring, but just couldn't get excited about spending that kind of money to end up with a stock truck I couldn't afford to mod so it made more sense for me to keep it and put a little into it instead. Besides, this truck has been babied anyway. None of this has happened overnight, and its still waaay cheaper than a new one.

 

[blk smoke lb7]

Yes I did read, but as coco said, 1350* ALL DAY on LBZ pistons, not just a few minutes. You really don't have an issue IMO, but a different tune could lower your egts some. But as I said, I don't think you have a problem but do what you want.

I dont see anything wrong myself 12 to 14 psi at 50% throttle seam proper.


I would agree the bigger tires are hurting you but the twins will help for sure with power and lowering the egts.

 

[Dirtymaxx03]

take that bitch off the tow tune and let er eat!

 

[bluessmax]

take that bitch off the tow tune and let er eat!

^^^i like the way this guy thinks!! Lol

 

[WVRigrat05]

take that bitch off the tow tune and let er eat!

X2, I pull 11k on my street tune up hills@70_75 mph, yeah the egts get up to 1400_1450 but the tow tune isn't much better so i rip on it. Any grade over a half mile i have to let out of it or it goes over 1500 even on the tow tune. 35's and stock gears kills egts. Mine are higher than most unloaded.

 

[DMAXchris]

Not sure about the lb7 pistons, but I have been told that LBZ pistons are rated for 1350* continuous(all day long)

ACTUALLY...It's the Garrett turbo that is rated for that temperature and a 5 minute duty cycle pulling max GCWR up the longest grade in the country.
I really really wish I wouldve saved the article from Garrett!

It has nothing to do with the pistons. :thumb: They can let go whenever. Mine cracked while cruising at 75 on the highway.

 

[firefighter13]

ACTUALLY...It's the Garrett turbo that is rated for that temperature and a 5 minute duty cycle pulling max GCWR up the longest grade in the country.
I really really wish I wouldve saved the article from Garrett!

It has nothing to do with the pistons. :thumb: They can let go whenever. Mine cracked while cruising at 75 on the highway.

Yeah, that's the impression I had too. I'm just not comfortable subjecting it to high egt's for more than a few seconds at a time. Not only hard on pistons and valves, but have you ever noticed how hot your oil gets and how the pressure drops with long pulls at high egt's? Not a fan.

Hopefully the twins will help with the whole situation.

 

[joelykool]

Twins are the way to go if you're worried about egts...I had an ats4000 turbo however, and with the right tuning, I couldn't get my lly over 1100 degrees. A lot of it has to do with tuning!

 

[arneson]

Twins will help everything but oil temps. Look into a gauge if you dont already have one and some sort of cooler. There are a few threads on coolers and options.

 

[mb1]

I have 2 suggestions: one is to try and pull a little more speed ( rpm ) I find the EGT comes down nicely when I run it closer to 22-2300 rpm, in spite of the added speed.

Second suggestion: try a few hills on a bigger tune and see how it runs. You obvs aren't running it pinned up the hill so maybe the hotter tune will have different timing / pulse to lower your EGT. It's worth a try.

Third suggestion: twins I'm pulling 35# at 2200 and 70 mph towing a similar load haha.

 

[firefighter13]

Haha! Yeah, twins on order from SDP! Can't wait! Also found 2 bad injectors this week after only 30k kms, suspect that the GM tech contaminated them when he installed them. Soooo, between that and the twins and an LBZ CP3 I am pretty sure it will be a whole new animal