2500 Suburban

[rabfan]

Hi,
We purchased a 2500 6.5 TD suburban last year and the wife loves it.
She mostly uses it in her 5 mile radius around the house to bring the kids to school and run errands. We don't put a lot of mileage on it at all.
We also use it to tow our travel trailer out to the camp ground on weekends for 4x4 ing (with my toyota, not the sub)
Recently we upgraded from our 42 year old 14ft trailer at 2500lbs to a newer 19ft trailer weighing in at 4000lbs.
While the sub had no problems pulling the 2400lb unit I was rather dissapointed at the performance pulling the 4000lb trailer.
Cruising at 95km/hr on flat roads with the occasional shallow grade the truck would slow significantly. I'm not a big fan of matting the throttle but even foot to the floor the truck was not pulling away positively. Temperatures were steady at just over 90*C(194~F)
I do not have a boost guage or EGT Guage

Starts can be sluggish and smokey when cold. Only some cylinders firing. shutting the truck off and restarting gets all 8 clacking.

I also have new glow plugs to install but yet to do it.

The truck has the PMD relocation

Mileage shown as 220,000km but some records I've found indicate the truck has more than that... in 2007 there is an entry in a notebook for mileage at 178,000miles(285,000km). The truck was originally from the US.
I imagine it must be somewhere in the high 300,000km range in reality.

I have purchased the 4" exhaust from flow pro(they are located in my town in fact) but have yet to install.

Hopefully the diesel isn't just tired and worn out. I see a compression test in the near future.

I've ordered the Volume 1 and 2 tech articles and look forward to learning more about the vehicle.

upon purchase maintenance has included,

New disks, calipers and pads for the front
New ball joints upper and lower
fixed fuel leak in lines coming up over transmission to engine
Cleaned up the wiring relocation to the PMD
Driver's side power window switch assembly and mirror switch

I do my own maintenance.

[a5150nut]

rabfan,

Welcome to TDP. I was thinking my old 94 was getting worn out and contemplating major engine work. Puff of smoke at startup, hard starting, low power. Then I moved it one day to go get my propane tanks filled and it wouldnt start at all. Did all the checks, lift pump, filter, then cracked an injector line. No fuel. Checked the Fuel shut of solinoid and it seemed to be working. So I go on line and order a new PMD from Kennedy.

A few days later it arives and I put it on. Truck hasn't ran so well in a long time. I think before the PMD failed compleatly it had deteriorated and I just figured it was getting time for major work.

You should add the year of your rig to help us figure out what is up. But the basics, air and fuel delivery first. If your is an "s" model could be EGR problems to.

Lots of good info here. Be patient, others will chime in soon.

[Burgess]

the 2500 sub was....is an awesome road gathering machine. big red finally had decided she was to tired to run in november of this year past.......... 435,000 miles....420,000 +/- on the motor. everything else is in good shape and kept up to speed. so i decided to put a brand new american general back in her from jk along with a brand new exhaust system from him. we moved the phaser gears over from the old power plant and put on a new turbo and the larger oil cooler plus what ever else needed doing. need i say that big red is better than ever.........growling with a new low rumble and since i'm banging away at being 72 this year........if i can keep big red out of the ditch........based on what i got out the original 6.5 it should make my millon miles easy...........the sad part is that they'll probably want my driver's license before we both arrive at that point.

side bar.........gm put a new engine in big red because it was eating coolant at 32,000 miles way back under warrenty when it went bad in a town long away from home, but that is another story for another time. i will add.......it took my ten years to win the lawsuit to get gm to honor the warrenty.

with all of that however.........the big red 1998 2500 is the most awesome vehicle i've ever owned........landcruisers.......bmw's.......and what ever included. need to redo the drivers seat however.......lol.....

[phantom309]

does your new trailer catch more wind?
a 3/4 cross wind in alberta can take the power out of most things,.
i,d definitely put in a new set of injectors,.mine has only 4-5 glows working,.
but it only runs for 5 secs cold and then all are banging away with just a little smoke,then smoke is gone in 2-5 secs
.new squirts brought my fuel mileage and power up,.and judging by the blowby i have,and its pumping oil into the turbo intake, my motor is very tired.
opening the exhaust really helps,.you didn;t mention the year ,.but spring loaded wastegates help some too,.then the obvious thing is a chip for it,.

have fun!!

nick

[Big Green]

Without knowing the complete history on the truck I think I'd start with your exhaust, new glow plugs and new injectors.

Gauges can be a big help in troubleshooting it too.

Also check the lift pump to make sure it's running. I also presume the fuel and air filters have been replaced.

If the lift pump is not running or worn injectors are leaking down it can make cold starts sort of ugly.

Big Green

[rabfan]

Thanks for all the great responses guys. I was concerned I should have posted this in introductions.
I wish I knew more about the truck myself. It's a 1996 although the door and glove box have vin numbers from a 1996 1500 series pickup. Heavy scrutinization under the microscope has revealed that the rear driver's quarter has been repainted. Very well I might add. Someone took the time to source a colour correct door etc. Frame and b pillar structure show no repairs so my guess is cosmetic damage prompted a repair. It has a national park sticker from Wisconsin in the windshield. Speedo has been changed to a Canadian unit. Has an antenna mount on the roof near the back.
As per everyone's input I will change the fuel filter fabricate a better flowing intake, install the 4" exhaust. The lift pump is working as I used it to prime the system after fixing my fuel line leak. Cracking the t bar also produces a nice jet of diesel and a big mess in the engine bay. I'm guessing in addition to a bleed system that is the poor mans way to make sure diesel is getting to the pump under pressure.
Does the phaser timing mod make a big difference? I'm thinking I'd like to buy a new PMD relocation kit too. The wiring harness on this one is home made and kinda hacked looking.

[greatwhite]

A quick amd dirty indicator of engine condition is blowby. If you pull the oil fill cap off does it puff white smoke? Thats compression sneaking by the rings.

If it puffs white smoke out around the oil dipstick, you've got a not very healthy engine on your hands.

Not to bring you down, but my orig gm built 6.5 506 block died at just over 100,000 kms and the replacement "tough" 599 block 6.5 died 300,000 kms. Just worn out...truck has 437,000 kms on it now and runs a GEP 6500 optimizer.

[rabfan]

I'll have to do an idle check with the oil cap off and see if the crank vent is being excessively pressurized.
Just got my Diesel Page Vol 1&2 books and have started reading.
Also ordered an intake kit from Summit and another PMD relocation kit.
Also checked out my water pump and crossover housing. Looks like I already have the HO and dual thermostat set up. Good times.
I looked into the phazer timing set up but i'll have to wait on that purchase for a bit.
Also checked my replacement glow plugs....sadly they are Bosch units. I bought them from my buddy's VW shop(I'm a big VW rabbit guy). hopefully I can exchange them for the AC-60G units.

[Big Green]

The phazer gear can be a nice improvement on trucks like mine with timing chain issues from day one. They are also nice if you plan to turn up the timing since you don't have the slack in the chain to deal with. That said, a good new chain will also yield many of the same improvements.

If you do the chain, also replace the harmonic balancer and lower pulley. Both can create broken crankshaft issues. Would also be a good time to replace the waterpump.

As far as glow plugs, look for a set of the fast heat type. Kennedy has them as do others. Nice improvement over the 60G's

Big Green

[rabfan]

Nertz, just ordered the 60G's this morning. I actually already changed the harmonic balancer and pulley when I bought the truck because there was reciprocting vibration at idle. It's still there so I guess that wasn't the problem.

[rabfan]

I've been randomly getting a low coolant light warning on the dash. Coolant level is good. I've looked for a new coolant level sensor but don't see one listed on rock auto. Can anyone suggest a solution? Thanks

[Yukon6.2]

Try Cleaning it.
I'v heard of them getting dirty and sending a false signal.
Thomas

[rabfan]

Thanks Thomas

[Yukon6.2]

Should of elaborated.
Take the tank off and use some dish soap and hot water,one i heard of had a film of oil inside the tank.
Worth a shot.
Thomas

[rabfan]

Does the computer sense when the low coolant light is on and go into limp mode?

[rabfan]

Bought the 4" stainless turbo back(down pipe is 3") from alligator performance. Just went to have it installed today. Exhaust shop says it doesn't fit the suburban. They called the manufacturer, which is right up the street from us and they said they've never made an exhaust for the suburban.
Anyone know what's going on here?

[Yukon6.2]

Hi
The suburban wheelbase is a little different than all the other P/U's.
But there is no reason the system couldn't be adapted for the Sub.
Shorten or lengthen the pipe.
Thomas

[rabfan]

I installed the exhaust yesterday. I pulled the inner fender to change the glow pugs and fix some wiring done previously.
I can say for certain that the FloPro definitely isn't made for the Burb. The down pipe and first section fit fine. The third section I cut and used only 13" in the middle at one of the minor bends. Then muffler and tail pipe. I have a slight up curve at the tail pipe and will drill a small hole at the first bend to prevent water accumulation. It was tight at the rear strut, fuel tank, and to a lesser extent the upper rear body cross member just forward of the axle. I will add a small rubber bumper at the fuel tank bracket in case it rubs from vibration although I'm confident it will be ok.
None of the hangars lined up. I cut them all off and used the hangars from the original system.

[rabfan]

I think I'm ready for our trip.
4" exhaust
New glow plugs
AFE intake
New radiator
New coolant
Pyrometer
Boost gauge
Aux water temp gauge
New splash guards
New tensioner
New serp belt
New fuel filter

If this thing still can't pull my 4000lb trailer up a hill without deceling and overheating I guess the next thing would be injectors.

[rabfan]

Anybody want to buy a suburban?

[Yukon6.2]

What happened?

[JTodd]

No kidding. That was a quick turn around.

[rabfan]

It's not making power.

[Yukon6.2]

Hi Rabfan
Sorry to hear that,i know they arn't powerhouses stock,but you can make power with them.It looks like you have got a lot of the stuff in place to make some more power.
Mabey start a new thread to address the lack of power.Mabey a call to Kennedy Diesel might help.
I have a 6.5 in my tow truck and it gets the job done without any heat issues,it is a standard so i have complete control of shifting.\
Hopefully you can get it figgered.
Thomas

[rabfan]

Thanks Thomas,
I have another thread going currently. I suspect my turbo is functioning poorly. We are currently in Portland Oregon and I would like to try and solve the problem before the weekend and our journey home the following week.
RJ

[rabfan]

I replaced the turbo and injectors in the parking lot of a garage that was kind enough to loan me a compression tool.
Boost comes in sooner and goes to 9 lbs but I'm thinking my power is still low. Compression numbers were quite high so I suspect my timing chain needs to be replaced thus my timing may be retarded.
On another note, my A/C compressor pulley failed because my brand new tensioner was over tensioning my belt.
Replaced the compressor and lock wired the tensioner back so it is within the belt range. This brought back even more power and the temps are staying down. So far no more stopping on the side of the road on hills.
I installed a 16" electric fan on the new rad that I can turn on when things get hot. My family is calling this vacation the tour of all NAPA locations.