Hey Vortec Guys! / Sierra pickup / Suburban / Yukon etc - Finally has Index!

[rayra]

@Yroundrdn if you are cranking fine but no start, I second the fuel pressure concern. And it could be an early sign of impending fuel pump failure. Especially in these older vehicles. If it was MAF you'd be getting a code or a lean condition alert. Could also be the Idle Air circuit (IAC) plunger, described early in this topic. Simple fix / maintenance.
Too, possible water in the fuel lines if you are in a cold clime. Some alcohol-based fuel 'drier' additive might be a help.
That's all if you have good crank but no ignition.
The other real problem that's hard to find, the thin yellow wire on the ignition key switch. Part of the Passcode security circuit, breaking wire causes intermittent failure. Loss of signal and the computer will not allow ignition spark. Car will crank fine, fuel will spray fine, but it isn't going anywhere.
If cranking is itself a problem, start checking you ground connections, battery to frame, battery to starter, etc.

 

[rayra]

Any of the GMT800 mafia upgrade your alternators?
Ours is in good shape still, but its something I've been thinking about as my partner wants to put an inverter and fridge in her truck and its going to be getting a GMRS radio n stuff.

I'm shopping higher output solutions now. I'm getting a high pitch whirr that I think is coming from my alternator bearings, 145k mi. IIRC I have the midrange of the three factory ratings offered. But first I'm pulling the ALT and greasing its bearings to see if that's really the source of my noise. It MIGHT be my power steering pump, I haven't narrowed it down yet.

 

[rayra]

My '02 factory options are 105A, 130A, 145A.

The '05 Tahoe options are 145A and 160A, but I already know their back plug / connector is different, although their physical mounting is the same.

Rockauto has a 'PowerSelect' branded 253A 'new' for $119, for my '02 Sub, flagged as a popular part. The Delco 145A replacement is $160 new no core charge.

I have no idea how any vehicle factory power management might interfere. If at all. I'd sure like to grab the 253A, on the premise / guess that its idle output level might also be relatively higher than a factory-option 145A

 

[rayra]

Calling all GMT800 Mafia... Calling all GMT800 Mafia...

My Fuel pump has begun singing its keening death song. Shopping rockauto and seeking which brands to avoid.
The noise began after a 60mi trip last friday, with about a 1/4 tank of fuel. eeeeeeeeeeeeeee. Almost turned the vehicle off at a red light to confirm it was me, but last moment thought 'maybe it won't work again', so drove it home and did that shutdown in the driveway. Today it didn't happen, but been considering the issue for a long time so 'trust' is pretty much gone. I have AAA Plus, but don't want to deal with driving it until it fails. I'd rather do the replacement at a time and place of my own choosing. So I'm doing the shopping and I know a few of you have had trouble of this type, could use any brand feedback.

/and yes, I intend to go thru the vehicle floor, for the hell of it.

@CrazyDrei @Stryder106 @AA1PR @02TahoeMD @boll_rig @Martinjmpr @Burb One


eta and it's about time I put an index at the front of this topic, so big can't readily find anything

 

[vintageracer]

Just did a fuel pump in one of our Suburbans last week.

Buy the AC Delco pump from Rockauto and do the job once. Don't go cheap on a fuel pump.

It's not hard at all to remove the tank out the bottom and do the job the right way. IF you decide to hack a hole in the floor make sure you git it in the right location and you might as well put a hinge on the floor piece you cut out to make the job easier for the next guy!

If you decide to remove the tank out the bottom and the tank still has a lot of fuel onboard a cheap $8.00 fluid hand pump from Harbor Freight works great at pumping the tank empty to remove all that weight. You will need a GOOD 2 piece fuel pump line hose release tool to git the fuel and return lines to release off the old fuel pump not some POS plastic 1 piece removal tool. Remove the fuel filler neck from the tank fill hose at the quarter panel fuel door. Leave the big rubber fuel hose connected on the fuel tank when you remove the tank out the bottom. You may have to change the fuel pump electrical plug with the new plug supplied with the new AC Delco pump depending upon year model of your suburban.

 

[rayra]

I know I should do a Delco, just don't want to spend the +$80 over the Delphi. Got a lot of other things that need the cash spent on them. Got an alternator crappign out now too and was right in the middle of finally finishing my winch project.


Took the time tonight to make an index for this topic and put it up front


INDEX for the topic -

Roster of GMT800 folks in ExPo - https://www.expeditionportal.com/fo...pickup-suburban-yukon-etc.155266/post-2302987
EGR Oil Ingestion, Remediation - page1
Heater Core connection Ts - page1
KNock Sensors - page1+
Idle Air Control (IAC) & rough idle - pg2, 23
Brake Fluid Flush/Change - pg2
Instrument Cluster Bulb replacement - pg2, 19
Oil Pump Pickup Tube O-ring replacement, Tahoe - pg2+
Vent Blend Door Actuator Repair / Replace - pg3
Torsion Key Leveling Kit Install - pg3-6
Discussion of H2 Springs - pg6-7
Mystery Coolant Loss / CasTech 706 heads cracking & repair - pg8, 17, 30 follow-up
Spark PLugs, platinum, iridium - pg9, 23, 49
Oil Pump Pickup Tube O-ring replacement, Sub - pg9
Toyota Tundra V-6 DOHC Timing Belt change - p10
Vortec Knock Sensors and Limp Mode - p10
Sub Rear Coil Spring replacement - p11+
Ignition Coil diagnostics - p11-12
Inner Tie Rod Sleeves - p12, 14
Rear brake Pad Replacement - p13
Driver window regulator and motor repair - p13
Rear Suspension Bump Stops - p15, 29, 48
Discussion of Scan and Temp gauges - p16
Steering Wheel 'clunk' / intermediate shaft - p17
Steering components and sway bar bushings - p18
PowerStop GMT900 Front Brake swap - pg18, 35 follow-up
Instrument Cluster Stepper Motors - p18-19
Rear Hatch and window releases - p20
Alternator Issues and mid-series design change - p21, 50-51
POtential Transfer Case wear-thru issues - p22, 31
Refueling early cutoff / purge valve / vapor cannister - p22-27
Throttle cable slack adjustment - p25
Fuel Pump Replacements discussion - p28, 32, 33 how to cut floor
Oil Pressure Switch / Sender - p29, 34 re-work
Radiator Crack, Patch, Replace, cooling system refresh - p29-31
Transfer case actuator / solenoid replacement - p34
front wheel bearings / hubs - p34-35
Torsion Key crossmember mount bushings - p35-36-37 temp shimming, 38 homemade bushings, 39 dorman, 40 replacement
Control arm wear and discussion - p35
CV joint dismemberment / reassembly - p36
Upper Control Arm and CV replacement - p42
Trans Cooler install discussion - p42


And my own build topic has a lot of installs and changes to my '02 Sub.

 

[CrazyDrei]

Calling all GMT800 Mafia... Calling all GMT800 Mafia...

My Fuel pump has begun singing its keening death song. Shopping rockauto and seeking which brands to avoid.
The noise began after a 60mi trip last friday, with about a 1/4 tank of fuel. eeeeeeeeeeeeeee. Almost turned the vehicle off at a red light to confirm it was me, but last moment thought 'maybe it won't work again', so drove it home and did that shutdown in the driveway. Today it didn't happen, but been considering the issue for a long time so 'trust' is pretty much gone. I have AAA Plus, but don't want to deal with driving it until it fails. I'd rather do the replacement at a time and place of my own choosing. So I'm doing the shopping and I know a few of you have had trouble of this type, could use any brand feedback.

/and yes, I intend to go thru the vehicle floor, for the hell of it.

@CrazyDrei @Stryder106 @AA1PR @02TahoeMD @boll_rig @Martinjmpr @Burb One


eta and it's about time I put an index at the front of this topic, so big can't readily find anything

rayra,

First of all, don't cut the floor. If you have less than 5 gallons of fuel in the tank you can drop it yourself in the driveway, just make sure you unbolt and disconnect evap canister, takes less time than to cut the floor.

I am cheap and firmly believe in least expensive eBay stuff, but not fuel pump, go with AC delco. Another option is an OEM take out from a salvage yard with low miles. Also change your fuel filter, it might be the root of your problems. When my Fuel pump went out 5 years ago I had 1/4 mile warning in pressure drop, no noise, just poof stopped working.

Good luck.

 

[Hillbilly Heaven]

Fuel pump ain't the place to pinch pennies. Buy once cry once. Another AC Delco vote. First verify the correct pump assembly. There is a tag on top of the assembly. Mirrors and flashlight are your friends here. Rock Auto is my usual go to place if I can afford to wait rather than buying local. BUT. Check Amazon to save a few bucks. Usually you don't need to worry about Chinese forgery. Don't cut the floor drop the tank. Years of road dirt is piled up there. You want to able to thoroughly clean the area before releasing the lock ring. You don't want that crap falling into the tank.

 

[Overlandtowater]

I did the Bosch, Ive always had good luck with Bosch brand.

 

[Mighty Dodge Ram]

Thanks for the index reminder. ?

 

[Buddha.]

I changed my transfer case fluid at 100k and it looked awful, my diff fluids all still looked brand new.
Now at 130k I decided I should change the transfer case fluid again. It looked awful again. It's not burnt and brown like old transmission fluid, it changed from a pink to a dirty purple color. Is this aluminum from the chain rubbing into the case?

 

[Buddha.]

The hardest part about dropping a fuel tank is disconnecting the fill hose imo. I've been told that you can do it without disconnecting that hose though by just tipping down one side of the tank.

 

[Stryder106]

Calling all GMT800 Mafia... Calling all GMT800 Mafia...

My Fuel pump has begun singing its keening death song. Shopping rockauto and seeking which brands to avoid.
The noise began after a 60mi trip last friday, with about a 1/4 tank of fuel. eeeeeeeeeeeeeee. Almost turned the vehicle off at a red light to confirm it was me, but last moment thought 'maybe it won't work again', so drove it home and did that shutdown in the driveway. Today it didn't happen, but been considering the issue for a long time so 'trust' is pretty much gone. I have AAA Plus, but don't want to deal with driving it until it fails. I'd rather do the replacement at a time and place of my own choosing. So I'm doing the shopping and I know a few of you have had trouble of this type, could use any brand feedback.

/and yes, I intend to go thru the vehicle floor, for the hell of it.

@CrazyDrei @Stryder106 @AA1PR @02TahoeMD @boll_rig @Martinjmpr @Burb One


eta and it's about time I put an index at the front of this topic, so big can't readily find anything

Do the AC Delco. My original lasted 12 years before it went out. The cheaper brand replacement didn't make it 18 months. I put an AC Delco back in it.

 

[Stryder106]

I changed my transfer case fluid at 100k and it looked awful, my diff fluids all still looked brand new.
Now at 130k I decided I should change the transfer case fluid again. It looked awful again. It's not burnt and brown like old transmission fluid, it changed from a pink to a dirty purple color. Is this aluminum from the chain rubbing into the case?

If your transfer case is completely stock - then what you could be seeing in there is magnesium rubbed off the inside of the case by a sharp edged widget. It will slowly rub away the casing to the point that it creates a leak at the top - which you can't see - and then your transfer case burns up. There is an aftermarket blunt edged widget to solve that.

And why is your transfer case fluid pink? Don't you use the Blue fluid?

 

[Buddha.]

If your transfer case is completely stock - then what you could be seeing in there is magnesium rubbed off the inside of the case by a sharp edged widget. It will slowly rub away the casing to the point that it creates a leak at the top - which you can't see - and then your transfer case burns up. There is an aftermarket blunt edged widget to solve that.

And why is your transfer case fluid pink? Don't you use the Blue fluid?

I had to double check the fluid type.

Starting with the 2007 model year,
General Motors introduced a series of
new transfer case designs to replace
the New Venture Gear units they used
in the past. Built by Magna Powertrain
(MP), the new units are available in
three different models:
• Manual Shift (RPO NQG; models
1222/1225/1226)
• Electric Shift (RPO NQF; models
1625/1626)
• Auto (RPO NQH; models
3023/3024)
Several models are available
for each application, including the
1222/1225 and 1226 manually shifted
units, the 1625/1626 electrically shifted
units, and the 3023 and 3024 auto/
active transfer case models (figure 1).
All models use DEXRON VI fluid.
The models features are shown in the
accompanying chart.