New here and need some info. Picked up Used lifted 99 dually

[Guinness]

I just purchased a rather large truck and was wondering if some people knew what I was up against. Here is the info.

1999 7.3 SD dually crew cab 4x4
8 inch lift (may be 6 inch)
37 inch super swampers (yes there are 6 $$$$$$ )
Single Banks from the turbo back (not sure make, but it is definitely aftermarket)
turbo saver
6 or 8 inch tip

There has been alot of work put into this truck but I bought it at a dealership where they took it on trade and didnt want a hassle after the sale so they let it go kinda cheap (atleast I think so)

Does anyone know how I would research find out what lift is on the truck? I know there are probably hundreds of different makes and might be just banging my head against the wall there.

It looks like the previous owner was into tuning it and he has wires, lines, tubing all over and a couple dial (potentiometers) in the cab near the stearing wheel. A 3 pod guage set on the piller and boost on the steering column.

A few things I noticed about this truck is it must have originally been a manual transmission since there is a cutout in the carpet and a hole in the firewall. It also must have been an electronic transfer case and converted to manual since there are plugs just laying on the crossmember near the transfer case and the shifter and boot look new. I am asuming he had a donor truck for these parts since the truck works great, shifts real nice and the shifter on the column is factory.

There are 2 potentiometer dials hooked to something, I believe to be the maps sensor. The blue on the left controls the boost which I can get up to 25psi or so, the red one next to is supposed to control the injector timing (from what the dealer told me) but I have yet to see a difference when adjusting this knob, I dont know where to set it so I leave it in the middle. In between the knobs is a single throw toggle that I have no idea what it does.

The waste gate is disconnected, but still seems like it works? I can hear air escape when I let off occasionally, but I am concerned when I am really on it it sounds like a farty bearing noise that doesnt sound so attractive. Some ricer kid told me it was turbo backspin when he rode in it with me. Do the wastegates just sound funky on these?

The service engine soon light below the tachometer (I think thats what it says) flashes every once in a while Very quick - so quick you cant read it unless you can get it to do it again right away(at first I thought it was a shift light)

I plan on taking all the home made tuner stuff off of the truck and getting a real chip, not sure which one to get but also want to be sure I can go back to stock so if anyone knows what this guy might have done so I can undo it please explain.

This truck is kinda a bastard, it has yet to give me any problems. But I am still looking at it sideways trying to see what its gonna throw at me first.

 

[patrickc]

To idenify the lift this might be some good info. Skyjacker brackets are usually red, superlift is yellow, fabtech is usually blue or black, and trailmaster is usually grey or silver. 37 inch swampers should just clear in the front when turning with a 6 inch and have a little more room with an 8 inch. The best thing to do is measure the height of a stock F350 dually and that will at least give you a baseline measurement. (an F350 single rear wheel should be close to the same)

Really there is no need for anymore than 5 guages Egt temp, Boost psi, Transmission temp, Fuel pressure, Oil pressure. The fuel pressure and oil pressure are really necessary when you start to do some serious mods such as injectors but are also nice to have.

The air that you hear escaping from the turbo (farty noise, turbo backspin) sounds like what we call turbo surge. Sometimes it will force air back out through the air intake. Basicly it is caused when too much load is put on a stock turbocharger. You can buy different compressor wheels and housings for the turbo to cure this problem.

I would remove all of the stuff you don't want and then cleanup all of the messy wiring and hoses. (organize them under the hood) That would be the best place to start.....I think???.....

 

[Guinness]

thanks for the info, I will hunt down wether its an 8 or 6. The lift is black and looks real nice (per my diesel truck buddy) since its not blocks and the pinions look set at the right angle to him. The front has 2 shocks, but someone went crazy with undercoating or paint so I am not sure they are truely black if you know what I mean. It has dual stabilizers and helper bags in the back, not sure if thats part of the lift though.

I have plenty of tire room other than turning left, I believe the left tire hits the leaf spring.

Do you recommend the chips tuner combo you have? Im really not digging the wiring the guy had done but it seems to work perfectly.

 

[BamaSixGun]

welcome guiness, now go break some records.

 

[patrickc]

I have not had any hick-ups with chip-tuner combo the best thing is that the bullydog module is completely adjustable while driving down the road. The combo seems to work for me but everyone has there own personal preference.

 

[Guinness]

welcome guiness, now go break some records.

Im hoping to not break the bank paying for fines and fuel in this thing LOL

I will have to get some pictures to put up its baddass

 

[Guinness]

The air that you hear escaping from the turbo (farty noise, turbo backspin) sounds like what we call turbo surge. Sometimes it will force air back out through the air intake. Basicly it is caused when too much load is put on a stock turbocharger. You can buy different compressor wheels and housings for the turbo to cure this problem.

I would remove all of the stuff you don't want and then cleanup all of the messy wiring and hoses. (organize them under the hood) That would be the best place to start.....I think???.....

That is what my diesel truck buddy said it might be, but I kept thinking he meant it would run crappy when it was doing it. I can live with it doing it, will it cause a problem you think??

I plan on spending a weekend taking off the stuff to redo it, but I would like to not have to drive the thing with 4 37" tires out back with stock power. Im pretty sure it has stock ratio rears in it, any idea what you would recommend for gear ratios with these size tires? I plan on going down to 36 or 35's at the next change. Something a little more reasonable.

 

[patrickc]

Turbo surge over time can cause turbo problems but it is not something to worry about right now. With a proper chip or programmer in truck it will help the turbo surge problem. Depending on how far you want to go with the mods it is a good idea to upgrade/ update the turbo. (compressor wheel, housing, complete turbo) If you just do a comp wheel and housing it will give you faster turbo spool up and cure the surge problem.

I have 4.56 gears in mine running a 38 inch tire in the summer months. The 4.56's are perfect for the 38's. For a 36 or 37 inch tire I would go with the 4.56's but a 35 inch I would go with 4.11's. I noticed a big difference when I re-geared my truck you'd be surprised on how much power you get back. You can go with 35 inch tires and 4.56 gears it will just rev 150-200 rpm's higher at hwy speeds than 4.11's which naturally hurts fuel mileage a little bit. I run 35's in all winter on my truck with 4.56's and average about 15 mpg on the hwy. (65-75 mph)

 

[Guinness]

Thanks for the advice, I changed the batteries today since it wouldnt start cold, I also changed the fuel filter up on top of the engine. I did some research and found out the back relay on top is the GPR but what is the one near it in front?

I am thinking about going with the predator downloader since it changes the shift points, can fix the tire ratios for the speedometer and the rest of what these things normally do.

Also me and my diesel buddy are trying to figure out why the previous owner has the 10k mod (via a potentiometer) and an air regulator going to the mass air flow sensor, arent these redundant? Im thinking he did the regulator first, then found the 10k mod.

The waste gate vaccum line is definitely unhooked and plugged onto one of the boost tube clamps, should I hook this back up when I program the puter or just do it now, Im not sure what it does but I dont want it to hurt anything-

 

[patrickc]

The relay in front of the GPR should be the starter relay. If you are going to use a predator downloader I would get rid of the 10k mod and the air regulator. All that they do is trick the ecm to send more fuel and modify injector pulse. They are pretty much pointless with a good downloader/programmer it does the same thing except properly.

The wastegate vaccum line that is disconnected controls the wastegate accuator (valve) I would make sure you plug it back in. There are different ways to modify this valve rather than just unplugging it. This might also explain why the turbo is surging (farting) so much as there is nowhere for the boost to go when you back off the gas or when transmission shifts.

It sounds to me like the previous owner was trying to get as much power as they could while on a cheaper budget.