$oC@l CTD

Picked up my buddy's modified 1972 Jeep Grand Wagoneer yesterday morning. It has the stock 350 removed and replaced with a Cadillac 500/tranny setup. Has 4.11 gears, Dana 60s front and rear, 4" superlift with ProComp shocks and 33" ProComp mud terrain tires on it. The stock vehicle weighs about 4300lbs, so I would guess that after his mods, he is a little closer to 5K at the most. The trailer is a dual axle steel flat bed open 18' car hauler (weighs I would say between 2-2500lbs at the most). So I am looking at approximately a 7500lb load MAX and I would assume that is guessing high.

The pull went down from highway 94E and ended up at the Pine Valley road exit off of highway 8E. For all you southern Californians, you know that approx 15-20 miles of that trip is 6-8% grades all uphill to an elevation of about 4200ft. I had 4 people in the truck (approx 7-800lbs)

I turned both of my boxes off so that I was going off of stock power/fueling (minus exhaust and intake which only help flow/temps and add a few hp/tq.

My engine temps didn't get above 210 degrees...so that's good. My tranny temps didn't get above 187, so that's good. I was holding down about 36psi for most of the grades. I pulled the grades at 70mph (2100 RPMs) and pulling wise, the truck was flawless. My speed didn't drop ONE mph the whole way up. The only thing that kind of got me a little concerned was slowly but surely, my EGTs worked their way up to 1402*. It took a little while and I was only at those temps for about the last 2 miles of the grades, but stock with the amount of weight I was pulling, those numbers are getting up there and to be honest, I am curious as to how you guys pulling 16K toy haulers are maintaining safe numbers.

Opinions?

bkrukow

My stock 04.5 6 speed would get up to around that point pulling 8% grades in Colorado. It never went above it but it would get up there and stay there most of the way up the hill.

$oC@l CTD

How much weight did you have behind you? My only concern is if I can reach 1402* over a few mile span with only 7500lbs MAX behind me, what should I be expecting to see when I get my 12-14k toy hauler in the next couple years?

JuzPlaneKrazy

Derek you won't have any problems with your truck pulling a 12K ToyHauler.
I'm running the Quad XZT tow box with the Commander and pulling the 5frwy Grape Vine with my truck and Toy Hauler thats 14.5-15K is fine. I use level 2 & 3 which is 40 and 65 HP and my tranny stays at 185*+/-, EGT's around 1100-1200* and boost can hit 39-40 but avg. is about 36psi.
I've tryed different settings and gear placement and now understand that my truck runs best going up that grade (which is a nasty grade) in 2nd gear and in tow mode and on level 2, seems to fit best. And with those settings I run about 2300rpms / 45mph and all temps stay in check. Level 0 just doesn't have the Pop I need, the extras HP at level 2 give's me what I need to keep speed up and have a tad in the bank if needed. Level 3 is good to, but EGT's and boost can rise real quick.
I was also unhappy with my Jake, but found it also needs 2nd gear and rpms around 2300-2500 to be effective, and now I'm more than happy with the complete settup pulling my trailer. It took some playing around and changing settings to get the rite combo to work with what I've got, thanks to Pauly explaining things a little bit to me about the chip and brake.
IMO, get a EB Brake, airbags, stay under or at 14K and your good to go.

06' 3500 Mega Cab SRW & 39 ft KZ New Vision Toy Hauler

$oC@l CTD

Man, you MUST have 3.73s or big tires...In 3rd Gear (drive O/D locked out) I am at 2500RPM at 55mph (I have 4.10s and stock 265 sized tires). If I were to stick it out in 2nd Gear, I probably wouldn't be able to get over 35-40 (I have never tried it)...I could have turned my boxes on, but I first and foremost just wanted to see what kind of numbers I would be looking at basically stock towing...after seeing what I saw, I would be kind of worried about turning the fuel up on my stock turbo...the truck pulled GREAT, I would just prefer lower EGTs with a load as light as mine regardless of grades. I could understand seeing 1400* with a full 15K behind you, but 7.5k?

ptgarcia

Nope, Joe has 4.10s and 265s.

If you want to stay cool, let up on that right foot. You're not going to pull a 6% grade with 8000 lbs in tow at 70 mph and keep EGTs in check. To be honest, I'm surprised you stayed as cool as you did. Wanna run cool? Slow down.....

$oC@l CTD

Guess I'm failing to understand...my engine wasn't lugging. I was at about 21-2200RPMS the whole time and 36psi averages. Correct me if I'm wrong, but isn't 21-2200RPMs and 36psi the same load on the engine whether you're going 50 in drive or 70 in overdrive?

I could see high temps if I was trying to pull the grades at 60mph in overdrive at 17-1800RPMs and 20psi lugging the motor...

On a side note, once we were off the highway and down near campo, I locked OD out because you simply can't go fast back in those windy back roads, and even at 50mph coming up some of those hills, I was seeing 1250-1300 and am confident that if they were to have lasted 10-15 miles like the grades on the 8E, it would have slowly gotten itself back up to 1400 again...

JuzPlaneKrazy

Yep I have the lower gear. Do you run in Tow Mode? I would think you would be able to keep EGT's down more with the taller gear. I can tell you this if I run stock I get less out of the truck and the EGT's go higher and I can barely keep over 40-45mph with my gearing. I started playing with the box and gearing and saw a point where I got the added juice I needed for more mph and the EGT's came down, but as I said if I go to max level 3 and start to push it the EGT's and boost are harder to control. I also found I was trying to get more out of the truck than what it has by trying to run at 55mph and over. The truck doesn't have it to give with my gearing. I've learned now that with a beast trailer like mine behind me I'm way better off keeping my foot out of it and be happy and safer running in the right lane at 45-50 mph with a little in the bank up those long grades.

JuzPlaneKrazy

Ya I did think that, (4.10s) intell I dug thru the paper work. Salesmen will tell you anything as we all know. After that trip to Lake Cachuma I knew for sure.
At any rate your rite about that heavy foot deal. It was a balance I needed to find before I was able to keep all temps,rpms and speed in tach. All part of learning the truck. Now back to the WW Toy hauler, heck, stock I could fly up the Grape Vine, but after I added another 8K behind me things changed a bit

ptgarcia

No, its not the same load. You have less gear reduction in overdrive which makes the engine work harder to move the load. It's the same principal as rear end gearing.

$oC@l CTD

I kinda figured that you had 3.73s if you were running 2300RPMs in 2nd gear at 45mph. At 45mph in my truck, I'm running about 2000RPMs in 3rd gear (drive with OD locked out). I wasn't really worried about being at 1402* because I knew that I was just about to the top of that grade, but if I had never done that stretch before, it would have concerned me a little bit not knowing when the end was near. I guess that the next time I'm loaded over 5K at taking that grade, I will drop down into 3rd, keep OD locked out and give her a try at 2500RPMs at 55mph..see what kind of numbers I get that go round. Might even try to turn the Puck on the lower setting and the Juice on 1 or 2...I can always turn one or the other or both off if temps start getting crazy...

$oC@l CTD

So do you think that 55mph at 2500RPMs in 3rd gear would suffice?

$oC@l CTD

Yeah, I was just getting ready to say...it's tougher for you to keep temps in check than it was for me yesterday...you're hooked to TWICE the weight if not more. I guessed high on the weight of the load I was pulling. And that 8E grade isn't as bad at the Grape Vine either...

ptgarcia

Give it a try. I bet it cools you down. If not, make your next mod a 62/12 or 62/14 turbo

JuzPlaneKrazy

I would try a few different settings, it can't hurt. Once I felt comfortable playing with the box while towing it made a ton of difference while towing, in temps/rpms & speed numbers.
I was really stressed out at first too, I couldn't get any real speed, rpms, and things where going haywire temps thru the roof. Just like Pauly said don't push it, your towing, it's not time to hammer down and go 65-70mph, I wanted to keep that 55-60mph + thing going too but it ain't going to happen for me with 15K behind me.