2012 Tahoe SSV

[coolvermicelli]

Hi folks!

The PD in the next town over were auctioning a few vehicles, including this 2012 Tahoe SSV, I placed a fun low-ish bid not expecting to win and somehow ended up winning. Total cost was about $7500 after sales tax & registration fees, car have 83.5k miles and 5.2k of engine hours. Now, I don't know jack about these cars, so I really need some advice.

1 - Given the mileage, should I just change trans & differential fluids now? Tahoe manual says to change these fluid at 97.5k but not sure if it applies here.

2- There are few cables & wiring for the lights & siren and I think they're all functional. Is there anything I can do aside from just tucking them away?

3- Driving home yesterday on 2WD, the car cruise smoothly up to 60 then seems to "stall" out, as in I have to pedal it a little harder to get it up to 70, is this a normal thing with the car?

4- The car shakes slightly & make slight metal scrape noise when braking but I'm guessing it's due to pads/rotor, but just want to put this here in case anyone want to check anything else.

5- Should I seriously consider AFM delete if I want this car to last a while?

Thanks in advance.

 

[Joseph Garcia]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Nice find!

A lot of folks here have PPV's, so you can get a lot of advice from them, and they will chime in.

@Fubar0715 is one member I know who has a PPV.

 

[Marky Dissod]

The PD in the next town over were auctioning a few vehicles, including this 2012 Tahoe SSV.
I placed a fun low-ish bid not expecting to win and somehow ended up winning.
Total cost was about $7500 after sales tax & registration fees, car have 83.5k miles and 5.2k of engine hours.
Now, I don't know jack about these cars, so I really need some advice.

1 - Given the mileage, should I just change trans & differential fluids now? Tahoe manual says to change these fluid at 97.5k but not sure if it applies here.
2- There are few cables & wiring for the lights & siren and I think they're all functional. Is there anything I can do aside from just tucking them away?
3- Driving home yesterday on 2WD, the car cruise smoothly up to 60 then seems to "stall" out,
as in I have to pedal it a little harder to get it up to 70. is this a normal thing with the car?
4- The car shakes slightly & make slight metal scrape noise when braking but I'm guessing it's due to pads/rotor,
but just want to put this here in case anyone want to check anything else.
5- Should I seriously consider AFM delete if I want this car to last a while?

At an average lifetime speed of 16.06MpH,
1. yes, I'd DEFINITELY change the ATF, differential, radiator, and any other fluids you feel like refreshing.
2. If they truly are functional, someone with more SSV experience will help you out with those.
3. Did you check axle & hub bearings? Any other checks? Pretend you're a mildly paranoid pessimist.
4. See #3.
5. You should have Engine Half@$$ disabled IMMEDIATELY, preferably ASAP.
Best bang for the buck is an ecm AND tcm tune, plenty of other reliability / durability benefits.
For the time being, get Engine Half@$$ disabled any way you can.
The sooner you disable Engine Half@$$, the longer the TCC will last, the longer the 6L80 will last.
(Read that it can be disabled by disconnecting an electrical connector at the brake booster?)

The difference between the 'fun low-ish bid' you made, vs what this truck should've actually cost ...
Whatever that difference, spend it on preventive maintenance & repairs.

 

[coolvermicelli]

At an average lifetime speed of 16.06MpH,
1. yes, I'd DEFINITELY change the ATF, differential, radiator, and any other fluids you feel like refreshing.
2. If they truly are functional, someone with more SSV experience will help you out with those.
3. Did you check axle & hub bearings? Any other checks? Pretend you're a mildly paranoid pessimist.
4. See #3.
5. You should have Engine Half@$$ disabled IMMEDIATELY, preferably ASAP.
Best bang for the buck is an ecm AND tcm tune, plenty of other reliability / durability benefits.
For the time being, get Engine Half@$$ disabled any way you can.
The sooner you disable Engine Half@$$, the longer the TCC will last, the longer the 6L80 will last.
(Read that it can be disabled by disconnecting an electrical connector at the brake booster?)

The difference between the 'fun low-ish bid' you made, vs what this truck should've actually cost ...
Whatever that difference, spend it on preventive maintenance & repairs.

#1 I'm changing oil today, it hasn't gone bad (looks darkish yellow) yet but might as well. ATF dipstick looks ok, slightly darkish red, I'll pump out a quartz or two from above & top up, will just do this periodically over the few weeks to refresh the fluid & change filter once it hits 97.5k, the transmission pan drop being blocked by the exhaust makes me really don't want to do it myself. Differential & radiator I'll take care of this summer.
#2 I'm hearing tiny sirens when I flip the switches in the car, I guess I just need to hook up a sound system of sort, but I don't really have any reason to make it functional I'll just leave it as it is.
#3, I'll drive it more today to feel the car out, maybe just me being paranoid.
#4, I found the cause, the rear rotors & brake pads were all worn in, already ordered replacements for that.
#5 AFM disabler is on the way, I have to say the lifters potentially being a problem down the road do have me concerned, but I guess that's for down the road. For now I'll save up for a tune.

 

[Marky Dissod]

The other thing that seems to delay lifter / cam lobe problems is
changing oil & filter more often than GM's Oil Life Monitor suggests.
GM recommends oil changes when it hits 15% (NOT 0%!)
but never over 7500 miles, and never over 1 year regardless of miles.
FYI, most NYC cabdrivers / livery / chauffeurs apply 'skew' to the Oil Life Monitor:
Mostly all highway miles (NOT NYC), change oil & filter @ 17%, NEVER over 5000 miles.
More highway than local miles, change oil & filter @ 20%, NEVER over 4000 miles.
More local than highway miles, change oil & filter @ 25%, NEVER over 3500 miles.
Mostly all local miles (LOTS of stop'n'go / idling / restarts), change oil & filter @ 33% -
NEVER over 3000 miles.

You'd be surprised that most NYC cabdrivers have ZERO lifter / cam lobe issues before 175,000 miles.

 

[coolvermicelli]

Just a little update, did oil change today, oil from drain pan look actually worse than it was on the dipstick, much darker. I measured 5 qt came out, so I put new oil in, turn on the engine for a little bit, then drained another 2 qt, in total used 7 qt of new oil.

Pumped ATF fluid out from dipstick hole, fluid was dark red, didn't look too bad, pumped out 5 qt, put in 4, I think it was overfilled to begin with, going to keep an eye on trans temp and top off another qt if needed.

That said, I'm not sure if there's a proper way to check dipsticks or not because both the oil & ATF dipsticks are always over the marks for me.

Now the fun part, rear rotor & brakes were a pain to do, lug nuts and caliper bolts were stuck on hard, took 2.5 hours to get the job done. Car now brakes whisper quiet and no more weird vibrations. All that's left is change out air filters, which I'll get to tomorrow since it was dark by the time I'm done with brakes.

Going to bring the car to a GM mechanic in town to do ATF drain-fill as well as differential & transfer case fluid in the summer, I think I have enough fun crawling under the car lol.

 

[Marky Dissod]

... not sure if there's a proper way to check dipsticks or not because both the oil & ATF dipsticks are always over the marks for me.

Transmission (which warms up after engine by about 5-15min, depends on how cold outside) must be up to operating temp.
Pull out dipsdick ( ), cover tube with something. Clean dipstick off as best you can.
With engine idling, shift into D, then R, then D, then R, until you get bored, then shift into Neutral, then D, then Park.
Clean dipstick off again, THEN insert into tube with no haste, then remove.
ATF temp affects reading; within NORMAL temps (167F-212F), hotter is higher.
If it's within the normal window at normal temps, you're good.
If you drive like an arsejack, SLIGHTLY more ATF than needed is ok, but a higher capacity pan is better.
Helps to have contrasting light environment. Forgot which color light works best on ATF.

Excess motor oil is bad because it foams, and air is a schidty lubricant.
It's ok to run 1/2qt low if you drive gently.

 

[RooTBeeRthe1st]

As long as none of the wires are hot, tuck them or remove/chop them out.

100% afm delete...at the very least, get a tune that turns it off.
I have 200k mi on my ssv, the 2nd 100,000 I have kept afm off in the computer and no issues yet...I also regularly wring it out to 6,000rpm maybe 6,500 even though it doesn't make power there.

Definitely not a bad idea to change all those fluids, especially since you don't know the previous service history.

 

[RooTBeeRthe1st]

#1 I'm changing oil today, it hasn't gone bad (looks darkish yellow) yet but might as well. ATF dipstick looks ok, slightly darkish red, I'll pump out a quartz or two from above & top up, will just do this periodically over the few weeks to refresh the fluid & change filter once it hits 97.5k, the transmission pan drop being blocked by the exhaust makes me really don't want to do it myself. Differential & radiator I'll take care of this summer.
#2 I'm hearing tiny sirens when I flip the switches in the car, I guess I just need to hook up a sound system of sort, but I don't really have any reason to make it functional I'll just leave it as it is.
#3, I'll drive it more today to feel the car out, maybe just me being paranoid.
#4, I found the cause, the rear rotors & brake pads were all worn in, already ordered replacements for that.
#5 AFM disabler is on the way, I have to say the lifters potentially being a problem down the road do have me concerned, but I guess that's for down the road. For now I'll save up for a tune.

You can sneak the pan out despite the exhaust. Just get crafty and expect some fluid to make a mess.