1998 k1500 silverado - 170k miles - new owner - maintenance

[user5116]

hi everyone, new to the forums and not experienced in DIY maintenance. i have questions, hope i'm putting this post in the right place.

i just bought a 1998 silverado k1500 z71, 168k miles on everything, it has the L31 5.7 vortec and the 4L60E. i am 4th owner of truck. the 3rd owner had it for about 10 years and put less than 40k miles on it. it was garage kept for the majority of its previous 10 years, so the body is real straight and it has minimal rust, which makes it a bit of a rare find along the rust belt of the midwest.

i want to do as much as i can afford in terms of preventative // catch-up maintenance, and im taking the assumption that a lot of the previous maintenance work has been ignored.

the truck has a few problems, and the biggest concern seems to be pretty bad oil leak coming somewhere out of the top side of the engine. i'll try to get some pictures of that later, maybe someone here has an idea about the most likely cause of this leak?

assuming that the leak can be fixed and that the motor is still good, my plan was to do these things in roughly this order:

MAINTENANCE
OIL & FILTER ---> CHG TO SYNTHETIC OK ?
TRANSM. & FILTER ---> DRAIN & FILL OR FULL FLUSH ?
FRONT & REAR DIFF ---> CHG FLUID ?
TRANSFER CASE ---> CHG FLUID ?
RADIATOR FLUSH ---> CHG THERMOSTAT ?
BRAKELINES ---> CHG FLUID?
POWER STEERING ---> CHG FLUID?

CHG FUEL FILTER ?
CHG AIR FILTER ?

BELTS & HOSES OK ?
BATTERY & ALTERNATOR OK ?

NEW PLUGS & WIRES ?

PO141 CODE

INSPECTION REQ.
NEW WINDSHIELD
REPAIR RUST ABOVE WINDSHIELD

NEW TIRES --- BFG A/T 285 75 16

EXHAUST SYSTEM --- FLOWMASTER



i was wondering if anyone here could step in and tell me about other common problems i should be looking for with the truck. other than the oil leak, the truck seems to be solid. drives straight, accelerates strong and shifts smooth. what else should i be looking towards in order to keep it that way?

thanks for any advice, i think i will be poking around the forums for a long time

 

[Rogue]

I would check the intake gaskets...when I bought my '97 with the 5.7 Vortec a little over a year go with 145,000 miles, the intake gaskets were leaking bad. Do a pressure test on the system and see if the pressure holds or it leaks anywhere. Also keep an eye on the coolant level and see if it's going down without any external leaks.

 

[kkirwan71]

hi everyone, new to the forums and not experienced in DIY maintenance. i have questions, hope i'm putting this post in the right place.

i just bought a 1998 silverado k1500 z71, 168k miles on everything, it has the L31 5.7 vortec and the 4L60E. i am 4th owner of truck. the 3rd owner had it for about 10 years and put less than 40k miles on it. it was garage kept for the majority of its previous 10 years, so the body is real straight and it has minimal rust, which makes it a bit of a rare find along the rust belt of the midwest.

i want to do as much as i can afford in terms of preventative // catch-up maintenance, and im taking the assumption that a lot of the previous maintenance work has been ignored.

the truck has a few problems, and the biggest concern seems to be pretty bad oil leak coming somewhere out of the top side of the engine. i'll try to get some pictures of that later, maybe someone here has an idea about the most likely cause of this leak?

assuming that the leak can be fixed and that the motor is still good, my plan was to do these things in roughly this order:

MAINTENANCE



i was wondering if anyone here could step in and tell me about other common problems i should be looking for with the truck. other than the oil leak, the truck seems to be solid. drives straight, accelerates strong and shifts smooth. what else should i be looking towards in order to keep it that way?

thanks for any advice, i think i will be poking around the forums for a long time

OIL & FILTER ---> stay with the conventional
TRANSM. & FILTER ---> just keep it full
FRONT & REAR DIFF ---> Check it and fill if need be
TRANSFER CASE ---> check and fill if need be
RADIATOR FLUSH ---> yes
BRAKELINES ---> leave Lone
POWER STEERING ---> leave alone

CHG FUEL FILTER ? Yes
CHG AIR FILTER ?yes

BELTS & HOSES OK ? Change if needed
BATTERY & ALTERNATOR OK ? Change I'd needed

NEW PLUGS & WIRES ?yes

PO141 CODE

INSPECTION REQ.
NEW WINDSHIELD
REPAIR RUST ABOVE WINDSHIELD

NEW TIRES --- BFG A/T 285 75 16

EXHAUST SYSTEM --- FLOWMASTER



sent from my glade air freshner

 

[Jrgunn5150]

That's basically the order I do things in. For oil, I use Shell Rotella T6, it's full synthetic, and only 22 dollars a gallon.

Depending on the color and smell of the fluids determines if I flush them or simply drain/filter. Brake fluid, I usually siphon it out of the master, then count on doing brake work in the future and that bleeding to take care of the rest of the fluid.

For example, on my new to me truck, I just changed the oil this weekend, next weekend I will do a filter and flush the transmission, week after that diff oils (make sure you can get the fill plug out first!), after that brake fluid, power steering fluid, then on to brakes, suspension pieces.

 

[user5116]

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thanks for the replys. here are a few pictures which might help show where the oil is building up and one picture showing where it is landing on the pavement below

 

[jkeaton]

You sure that's not power steering fluid? Mine had a similar leak pattern. It was the power steering reservoir leaking and getting blown back onto the engine by the fan.

 

[Jrgunn5150]

It certainly looks like powersteering fluid, it looks like that one line is leaking where it goes from metal to rubber maybe

 

[90halfton]

Id definitely leave the tranny fluid. If the tranny has 170k on it its probably relying on that thicker fluid to make it run right. Lots of ppl flush higher mileage trannys, only to change it out for a new one in the near future.

 

[Jrgunn5150]

Id definitely leave the tranny fluid. If the tranny has 170k on it its probably relying on that thicker fluid to make it run right. Lots of ppl flush higher mileage trannys, only to change it out for a new one in the near future.

This is absolutely a wives tale and bad advice, establishing a maintenance schedule as the OP would like to do is the correct thing to do. People who claim to have problems after flushes either, A. Waiting until they had a problem and then tried to fix it with a flush and fill, or B. used that POS machine at the quicky lube that forces fluid through the trans and doesn't address the filter at all.

No one ever advocates not changing engine oil to avoid problems....

 

[twomanymontes]

Definitly do not switch to synthetic. The gaskets from back then were not designed for synthetic oil back then.