Engine/Transmission (1998.5 - 2002) Help? Towing Issues

[SKuyper]

Let me start by saying I sold my GOOD truck... sold the 95 dually 12valve auto w 3. 54 gears which would pull my camper very well. Now, since I sold the dually, I moved the hitch over to my wifes 98. 5 3/4 ton 4x4 with the same gears and auto trans. The only mods this truck has so far is aFe cold air intake, Quadzilla XZT+ box (65-70hp) and a MBRP 4" pipe. The biggest problem is while the truck runs good on it's own, hook it to the camper, it's a dog. With the box turned off, it barely pulls the trailer at 60 on the level w OD off... hit a small hill, forget it! If I hit the mid position on the box (35 hp) and run it with OD off it will handle hills, decent but forget running OD & TC Lockup. If I hit the high position on the chip, I can run OD but if I push it, I can tell by tach movement that either the converter lockup or 4th gear will slip a little bit. I had no problem with the old 12 valve truck and auto transmission but I thought the 24v was supposed to have about 60 more hp than the 12v was bone stock??? What gives? Any Ideas? I had to replace the VP44 last summer due to lift pump failure, current fuel pressure is 12 at idle, could this be the problem? not enough fuel under load? There is dang little if any smoke at WOT outside of initial takeoff. Crap! even my bone stock old powerstroke ford that I had before the 12v dually, used to pull my trailer better than this truck will.

 

[hsmith]

Are there any codes and do you have gauges? I'm curious what the boost is doing or not doing under load. Also egt's numbers.

Glad I still have my 12 valve. Pulls out 37' Alfa Gold with ease. Had to throw that in. LOL

 

[Crash&Burn]

My stock 99 6-sp with 354's pulls a 29ft Glendale in OD with ease, moderate hills require 5th gear... . has original vp44----so far

 

[SKuyper]

Unfortunately I let my gauge pod go with the 12 valve truck... so I have to get something soon. There are no codes, no check engine light and the trans temp light has never come on in this truck. I do know my charge air cooler tube boots are a little on the soft side... especially the bottom front ones but there are no holes in them that I can see... it's possible they could be leaking under high load/boost conditions. My 34ft Dutchmen weighs near 8k dry... it has a single super slideout and a generator.

 

[blacksheepdiesel]

Yep, gauges would help with diagnosis. Really, pulling the load you have gauges are mandatory.

Do you have a boost elbow installed?

What size are the tires?

12 psi is good for WOT, it that's the case.

May be time for a transmission upgrade.

Godspeed,
Trent

 

[Bob4x4]

A boost elbow would cause the stock truck to derate

 

[SKuyper]

I agree that a boost elbow would cause a stock truck to derate but... I've got an XZT+ which is plugged into both the diagnostic port for the ECM and the MAP sensor... so it already does boost fooling so to speak... so... a boost elbow might do the trick... not really sure how a little orfice in an elbow in the compressor housing will cut pressure to the waste gate actuator... once pressure equalizes on both sides of the boost elbow... the gate is gonna open anyhow. I havent been sold on that one yet. A better idea would be a plug in the compressor housing... and a gauge to watch !

 

[SKuyper]

I think I'd probably better invest in a good converter with a low stall speed and solid lockup... and maybe some valve body mods to give me more clutch apply pressure... if anyone makes such for the Chrysler fusable link. Both are spendy ventures on ranch wages and I just got done getting JP at Shied's to build me a new VP44 this past summer... . he used to build all my tractor pulling pumps back when I did the NTPA thing in Missouri ... my lift pump was puking and smoked the VP... . one more thing I miss about my P7100 fueled 12 valve... . 48 psi fuel pressure !!! not this mickey mouse 10 to 16 psi crap we have to live on pins and needles over on a daily basis.

 

[JDecanter]

The 98 24 valve automatic had 40 less horspower than the New Venture. My old 98 five speed pulled 10,000 plus pounds with ease in 5th gear. I did notice when pulling into a strong headwind, it would detune itself to the point the speed would drop several miles per hour at wot. I could slow to about 60 for a few minutes or downshift and it would again return to normal power.

 

[SSolderitch]

I agree that a boost elbow would cause a stock truck to derate but... I've got an XZT+ which is plugged into both the diagnostic port for the ECM and the MAP sensor... so it already does boost fooling so to speak... so... a boost elbow might do the trick... not really sure how a little orfice in an elbow in the compressor housing will cut pressure to the waste gate actuator... once pressure equalizes on both sides of the boost elbow... the gate is gonna open anyhow. I havent been sold on that one yet. A better idea would be a plug in the compressor housing... and a gauge to watch !

correct, but it will add a time delay. Slowing up the time it takes to equal pressure balance.

 

[SKuyper]

On a long pull up a mountainside towing... especially in the state I live in, a boost elbow wouldnt do much... I'd get halfway up the grade and the waste gate will open anyhow at somewhere around 18-23 lbs of boost,and the truck will fall on its face... my old truck I had the waste gate disabled totally and I could get nearly 35 lbs out of the OE turbo... of course there was no computer and map sensor to de fuel the truck... just had to keep an eye on it. water temp, egt and transmission temp

 

[SnoKing]

One other thing to check is the throttle cable. Reach in and lift the pedal, if it goes up a inch of so, you are most likely not getting full throttle. Look at the upper end of the pedal and put a tie wrap or fishing split sinker on the cable to take up the slack. I noticed that my cruise control had more power than my right foot.



SNOKING

 

[Bob4x4]

correct, but it will add a time delay. Slowing up the time it takes to equal pressure balance.

The elbow has a bleed hole in it that will bleed off the boost before reaching the actuator

 

[Bob4x4]

On a long pull up a mountainside towing... especially in the state I live in, a boost elbow wouldnt do much... I'd get halfway up the grade and the waste gate will open anyhow at somewhere around 18-23 lbs of boost,and the truck will fall on its face... my old truck I had the waste gate disabled totally and I could get nearly 35 lbs out of the OE turbo... of course there was no computer and map sensor to de fuel the truck... just had to keep an eye on it. water temp, egt and transmission temp

If you have a fueling box and boost elbow you should be seeing more boost than that

 

[blacksheepdiesel]

I was getting 35psi out of my original turbo with a boost elbow all the way up any grade. My new stock turbo without boost elbow is only getting 24psi. Trust me, the boost elbow works!

Godspeed,
Trent

 

[SKuyper]

The 35 psi of boost I was referring to was on my 95 12 valve truck which I had disabled the waste gate actuator and plugged the pressure line feeding it. I haven't tried the boost elbow thing on my 98. 5 truck that has the Quadzilla box on it. I tried to find one on Vulcan's website but couldnt find one... wasn't it Vulcan that made em and sold em? At any rate, before I get too wild with fuel and boost, I need to change my fuel delivery system... get rid of the lethargic OE type pump. I dont have the chips to go with a FASS or AIRDOG and with the gumbo mud we have here, I dont know how long that fancy stuff would last hanging under the truck. . ( it's 4wheel drive the last 14 miles to the house if it rains more than an inch around here and the stuff will hang on the bottom for a month without a pressure washer job). I'm thinking of trying Holley's new 12-150 gerotor pump... less noise and more volume than Carter's P4601HP rotary vane pump at 150gph at 16psi, plus it's rebuildable and has an adjustable pressure regulater. Anyone try one of these mounted back by the tank?

 

[SKuyper]

Hey Blacksheep Diesel... I just noticed that you are from Vincennes, IN !!! Ever get over to Lawrenceville IL or St Francisville? We have some very longtime friends there. . BuchananFarms. know any of em? Maybe you know J Pezan at Sheid Diesel in Terre Haute? he used to build all my tractor pumps when I was pulling. I used to live in the Batesville IN area Ripley County... . Small World !!!

 

[blacksheepdiesel]

SKuyper,

Oh yea, go through those places quite often. Love going across the Cannonball toll bridge (old railroad bridge) with a 39' 5th wheel! I know who the Buchanans are but not personally. Also know JP but I don't think he is at Scheid anymore. So, from the Hardwood Capital of the world to Big Sky Country. Cool!

Godspeed,
Trent

 

[blacksheepdiesel]

SKuyper,

Have you thought about mounting a pump in the bed of the truck to keep the mud off? That is where my AirDog is mounted.

Godspeed,
Trent

 

[SKuyper]

Trent,
That would be a good place to mount a pump. . if I wasnt too worried about breaking it... I'd be a posterboy for Rhino Liner. . the crap that gets tossed into the bed, jacks, tools, diesel fuel tank during planting and harvest.
JP was still there last July when I roasted the VP in this truck... was kinda weird, engine would run great til it hit operating temp range... at 170 it would die like the key was turned off. JP told me the electronics were overheated, probably due to low fuel flow from lift pump ( imagine that ) Anyhow, JP sent me a VP via UPS Red... that was a year ago. He's been at Sheids a LONG Time
I cant believe the old toll bridge at St Francis... . is still standing let alone drivable . I worked for Art B. when I was a kid and hung out with Bill & Greg B. who lived at the big hog farm across Rt 1 from Art's house. I think the family owns pretty much most everything south of Lawrenceville ha ha... is the Marathon Oil Refinery still there? I heard rumors of it closing down? Is the Spot restaurant still by the tracks in Lawrenceville? It was a cafe made out of an old rail car... . course that was 30 years ago... probably gone.