2008 1500 with 4.8l

[sdeeter19555]

OK, thought I was getting out of this, but the company decided to keep this old work truck...it's a 4.8l, 4spd, 4wd, 3.42 (Gu6), G80, standard/long...typically work truck with Onstar? Has 180k miles on the clock, appears to have been neglected, not beat, but just neglected. I have no history, just noted it has had some maintenance like plug wires, etc. Had some issues, O2 sensor, the purge valve, etc., and all that was fixed. It runs amazingly well...I think it needs run hard as I think it idled around quite a bit.

 

The PS fluid was black, exchanged it twice and now it's just brown. Probably do this one more time.

 

The trans fluid is brown/yellow...it's not burnt. I tried to suck the fluid out through the dipstick, but that only netted about three quarts. Really don't want to drop the pan at this point. Confirm this is DexVI?

 

Cruise light illuminates on the wheel, but it doesn't engage (no light on the dash). Any suggestions?

 

I have some synthetic 75w140 gear oil to fill the differentials...yeah, it's not 75w90, but it's free. This will be tomorrow night's project. Is my understanding correct that the rear requires a cover pull and the front has a plug?

 

 

 

 

 

Sent from my SM-T350 using Tapatalk

[silveradosid]

you are correct about the front and rear diffs as for the cruise check to see if there are any codes stored or pending

[sdeeter19555]

you are correct about the front and rear diffs as for the cruise check to see if there are any codes stored or pending

Would a TPS sensor code cause the cruise not to work?

 

We got that and a fuel purge code, cleared them yesterday, drove for a little (about 100 miles), and the light popped on this morning when I started the truck...have not read it this morning.

 

I'm wondering if it's being stored and taking so many key cycles to pop the light?

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

Do the 2008s have reusable differential cover gaskets?

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

[sdeeter19555]

Ok, got a PO0496 for a high purge? That was the only code listed...

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

[j-ten-ner]

...Cruise light illuminates on the wheel, but it doesn't engage (no light on the dash). Any suggestions?...

 

Brake light switch. Common problem with the early GMT900.

20 bucks and 5 min of your time to swap it out.

 

so long

j-ten-ner

[sdeeter19555]

 

Brake light switch. Common problem with the early GMT900.

20 bucks and 5 min of your time to swap it out.

 

so long

j-ten-ner

That might be it...the brakes are actually applying before the lights themselves actuate.

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

[sdeeter19555]

Well, crawled under a little tonight (have a more pressing issue at hand).

 

There is no drain plug for the trans...so, keep sucking it out and refilling.

 

The rear differential cover is leaking, so that means even if it has a reusable gasket, it's bad. I'm going to use gray RTV.

 

The transfercase is easier to get to than on my 2500. Should be a slam dunk.

 

Now riddle me this, why are there restraint cables on the rear body mounts?

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

[sdeeter19555]

Got both codes back, sent it off to the shop for fixing (I don't mind doing the easy stuff, but it's the company's truck in the end). They are going to fix the issue with the two codes (EVAP and TPS) and see about the brake pedal switch and cruise.

 

Once I get it back, I'll finish the fluids and fit the toolbox.

 

Sent from my SAMSUNG-SM-G900A using Tapatalk

[txab]

Cruise will generally not set if there are codes present. In addition to brake switch, the cruise wiring may be damaged in the column.dash

[sdeeter19555]

Cruise will generally not set if there are codes present. In addition to brake switch, the cruise wiring may be damaged in the column.dash

I appreciate that insight. The brake switch (and pieces to eliminate the codes/CEL) will probably be as far as we take the cruise...it's more of a safety issue since the brakes will apply before the brake lights illuminate. If that fixes the cruise, great; otherwise it is still just an old company truck.

 

I'm looking for a reliable truck for point A to point B runs...I'm not even sure how long they plan to keep this one, which is why I'm doing some of the maintenance myself.

 

Sent from my SAMSUNG-SM-G900A using Tapatalk