sluggish pulling?

[shaggy10000]

I've had great luck getting help here with all my other problems before and it seems i have a new one. Maybe..
The truck is a 94 2wd longbed with the 7.3 idi and factory turbo and an auto trans. The rear end gears are the 3.55 i think it is. I know its not the 4.10.
I bought the truck specifically to pull my rock buggy on the weekends.
The buggy and trailer are right at 6000lbs verified by a scale.
The other day i pulled this about 20 miles out of town. The road out is mild hills and speed limit is 65. By mild i would say that most passenger cars would not require a downshift to make it up them. I on the other hand was struggling to make it with the OD on and the water temp was climbing rapidly. I have not turned up the IP and i doubt the previous owner had done it either.
Today i gave the trans a fluid and filter change since i suspected slippage. The fluid was dark but not really burnt. I also adjusted the FIPL sensor after reading about it on here. Made the truck shift exactly like it should. Man im glad it shifts right now. Towed to the same place today and this time i tried to run the hills with the od off. Temp still went up if i tried to keep it at 65-70mph and was nearly full throttle. Rpm's were around 2500. If i dropped down to 55mph the temp went down and of course went way down once on level ground. This is my first diesel and i have nothing to compare it too, but it seems like something is wrong. Shouldnt i be able to pull harder? or Is this normal for a factory setup of this age?
Any advise?
BTW i dont have a Boost or pyro gauge installed but the turbo seems to be working. I know i can hear it whistle when on the throttle

[JJFLASH]

Have you flushed your coolant system and blown/washed you rad out? I don't know a lot about the IDIs but they weren't really known for being powerhouses. I would say that if you can keep up with traffic tuggin 6000+ lbs you are doing pretty well.

[dakotajeep]

When your temps went up, how high on the guage did they go? Did your Overtemp light come on? If not have you verified the gauge is working properly? I installed after market guage to mine to know exactly hot the coolant was getting.

The big things are whether or not the fan clutch is engaging, water pump is seeping or if the coolant has been flushed recently.

Personally, I had an issue with mine and replaced everything. I waited with the radiator till last since it was the most expensive and thats where I should have started. Mine was just corroded beyond belief and wasn't flowing what it should have.

x2 on the fact that these aren't powerhouses. I wouldn't pull that weight in the hills in OD. But I do think you should get an EGT and Boost gauge to know more about what you have going on.....and a coolant gauge.



Good Luck

Thad

[shaggy10000]

I didnt let it get more than 3/4 on the guage. Never saw an over temp light. I wasnt trying to push it more than i needed to.
I guess i need to check out the fan clutch and give the rad a cleaning.
Then buy some gauges.

[FordGuy100]

A good coolant flush is a good place to start. Also, some cheapo gauges are nice to have (the three pack, water temp, oil pressure, volt). They may not be the best gauges, but they are multiple times better than the factory gauges.

I would also try to find another tranny cooler...if you buy one online find one that has the biggest GVW rating (26,000 pounds and up are good). A tranny temp gauge would be nice to have, but a good cooler can make that less of a problem.

As far as towing up the hills, if the truck is stock, then yes it will be a little sluggish. If you dont mind a loud pickup, I would straight pipe it. Cut the muffler out, and either run a custom exhaust of your choice, or get a piece of pipe to replace the muffler. The stock downpipe on these trucks arent the best, but its rather costly to replace them, so for the time behing you can leave it in there.

Also an air filter would be nice to add.

If you have the money, get a pyro, boost (15psi is really all you need, but if you buy a kit they will probably be 0-30psi), and tranny temp. Along with that a tranny cooler, and straight pipe it. Once you have those gauges, you can turn the pump up a little bit which will help a lot.

[shaggy10000]

I'm thinking about straight pipe. I have lots of 4" at work that i could get for really cheap. I have access to a machine capable of bending it and i have both a mig and tig welder. I should also be able to come up with a solution for a 3" downpipe as well. Unfortunately time is an issue for me right now. I have whats left of september to get ready for 4 camping/quail hunting trips in Oct and a deer hunt in Nov. That makes money an issue as well, but i plan to work on a set of gauges and a new fan assist tranny cooler. We'll see where that and a new exhaust gets me.

[shaggy10000]

Now that i think about it, if anyone has any pictures of the aftermarket DP it would give me some idea's.
Thanks

[shaggy10000]

Fan clutch seems to be working as it should. Still no time to flush the radiator yet but soon. Also have a pyro and boost gauge on the way with an "A" pillar pod to house them. should know more next week

[shaggy10000]

Wanted to update. I've been busy as hell and this got put on the back burner.
Anyway, i did some more towing this weekend. I pulled a 4000# camper with a 14 bolt gm axle in the bed. Bout' 700+ lbs. Same 20 mile stretch, I was getting about 6 mpg Was running 800 -1000 on the pyro in the flats and had the accelerator down to just before it wanted to downshift into passing gear. Nearly full throttle. Which got me to 65 mph. I should be able to pull this much weight in OD in the flats right?
I thought about the OD clutches slipping in the trans so i slowed it down a little steadied the rpm's and jammed the throttle. The rpm's stayed pretty consistent with the spedo.
The truck had a new IP on it just before i bought it. I have no idea if its been turned up or if the timing is right. A buddy of mine who is good with diesel's mentioned the Cat may be plugged. I checked underneath and it looks as if the cat was removed. There is a section about 3ft long that has flanges on both ends but it is the same diameter as the rest of the exhaust. So i believe someone else has bypassed it.
I should also mention that im running 3.55 gears
and i run about 4-5 lbs of boost at this speed. With a max of 6

I have never towed much with any other diesel so i really dont know what to compare it to. I will say this. My Wife's V6 honda ridgeline pulls the camper better. Somethings gotta be wrong.
How does this compare to some of you IDI veterans?

[itn69]

Maybe try posting on oilburners.net. Lots more IDI info.