Stock Vehicle Maintenance

[tinfoil_hat]

Might as well just go ahead and do those lower intake gaskets. It's just too common of a problem to ignore. You said you flushed the coolant system really well, which is good. Did you open the block drains? Mine were totally plugged even after a good flush.
Another thing to keep an eye (and ear) on is the belt tensioner. Best practice would be to change it when the belt was changed but you never know. If you decide to swap it, do the idler at the same time.

 

[Biggershaft96]

They get knife edged from the cam. Erratic timing and possible misfiring result, until eventual failure.

This happened to me, twice. Once on my truck waaayyyy back when i first bought it and my buddys 98. But neither of them actually got to the point of failure. Just bad misses from what seems like nowhere.

It would be ideal to do lower intake gaskets, valve cover gaskets, distributor, and mpfi injector swap all at once.

 

[jw_96]

Ok, I'm going to be "that guy" since there is no sticky that appears to apply or recent threads...

Anyway, I acquired my 98 k1500 burb last summer. Little backstory there, but essentially no useable known history on the vehicle. Runs great, typical oil seepages and whatnot here and there. Picked it up around 160k miles and currently around 165k miles.

So maintenance and I'm not talking regular oil changes, what do you guys do to keep these things running like a top?

At this point I've done oil and filter change (obviously). Transmission fluid drain and refill with new gasket and filter. Front and rear diff drain and refill, new gasket and limited slip additive in rear. Transfer case drain and refill. radiator flush 6x over or more since somebody at some point mixed regular green with the dexcool and it was nasty in there - new thermostat as well. Radiator hoses looked good. No noticeable cracks in fan belt either so it has been replaced recently. Checked brakes, checked u-joints, flushed brake fluid, flushed power steering fluid. New AC Delco plugs, and cap, rotor, and wires.

Tires decent for a bit longer, but are C rated 6 ply which sucks towing heavy. Wired in a 7 pin rv plug, weather tech floor mats in the front, and an ultimat dash carpet cover since dash is minorly cracked. And that's just about it.

What else should I do to it to get the most out of it? I fully expect a trans rebuild in the future because of the miles. Possibly rear diff rebuild and motor rebuild even further down the line but hopefully not until the 250k mark or greater.

Valve adjustment? Or leave that alone? Ignition switch is a pain, but is it going to become a real concern later on? Currently takes wiggling the key significantly initially to get it to go, then I can be cruising 75mph and pull the key out. Tumblers are obviously worn out, but if it doesn't typically progress to the point it won't even turn at all then I won't worry.

And that's it for now...

Well my ignition switch went out around 163000, but before it went out having a new key cut helped with wiggling

Sent from my Pixel XL using Tapatalk

 

[Bob L]

I make it a habit to give a squirt or oil on the door hinges and hood lock at every oil change too. It will save you from the dents in the hood from banging on it to open. Gets a few extra years out of hinge bushings too.

 

[someotherguy]

The ignition tumbler is pretty easy to replace on 1995-up, providing you have a key that works as you need to turn it to get it out. You have to remove the column plastics; start by carefully prying the bezel off the ignition switch. Then there are some torx screws recessed into the lower one. It hinges away from the upper, and then there's some external torx screws going in underneath the top one; if you don't have any e-torx bits you can usually get away with a small socket on those as they aren't that tight. Now you've exposed the column casting itself and you'll see a small hole above where the tumbler sits inside. Disconnect battery, turn key slowly until you see a tab appear in the hole. Press it with a pick and pull the tumbler out.

You must be registered for see images attach

As mentioned earlier 1998 is first year for Passlock antitheft on these trucks; you need to get a tumbler for a 1998 as earlier years will not work. It has the resistor in the tumbler itself for the antitheft, as opposed to it being in the key like earlier VATS antitheft some may be familiar with from Corvettes, Camaros, etc. from years past (on those you can see the "chip" in the key.) You'll need to do a security relearn procedure since the resistor is likely different in the new tumbler. Try to start the truck, it should stall out immediately and flash the "security" light. Turn key off. Now this next part repeat three times: Turn it back to "on" but do not start it. Let it sit 10 minutes. That should do it...it's been years since I've done one so you may want to 'net search that one for accuracy.

Distributor gear is problematic on *some* of the Vortec engines as they were improperly hardened from the factory. I agree with the "ain't broke, don't fix it" mentality on these as you need a good scan tool to properly set the timing once you've pulled the distributor on one of these engines; you cannot do it with a timing light.

Lastly from what I saw in your original post. Limited slip additive is a no-no. If you've got RPO code G80 on the option label in your glovebox, this is a locker (Eaton Gov-loc) - it is not a limited slip or posi; those were not offered in these trucks. Per GM service bulletin you should not use any limited slip or posi additives as they can cause the Gov-loc to not work properly.

Richard

 

[seanb98]

Might as well just go ahead and do those lower intake gaskets. It's just too common of a problem to ignore. You said you flushed the coolant system really well, which is good. Did you open the block drains? Mine were totally plugged even after a good flush.
Another thing to keep an eye (and ear) on is the belt tensioner. Best practice would be to change it when the belt was changed but you never know. If you decide to swap it, do the idler at the same time.

Sounds like I'll definitely be doing those gaskets. Can't be too bad of a job.

I did not open the block drains, I was not aware that there were any. Where are they? I did run the heater full blast both front and rear between each flush with a fill of clean water, and drove around for a bit each time. Thermostat was removed so water would constantly circulate. Repeated this around 6 times before getting mostly clean water out of the radiator drain.

 

[seanb98]

This happened to me, twice. Once on my truck waaayyyy back when i first bought it and my buddys 98. But neither of them actually got to the point of failure. Just bad misses from what seems like nowhere.

It would be ideal to do lower intake gaskets, valve cover gaskets, distributor, and mpfi injector swap all at once.

My engine is running great, but I'll definitely keep that in mind for if such a thing starts to occur. What kind of mileage were the engines at when it happened?

 

[seanb98]

I make it a habit to give a squirt or oil on the door hinges and hood lock at every oil change too. It will save you from the dents in the hood from banging on it to open. Gets a few extra years out of hinge bushings too.

Good point, I'm already in this habit as well. I usually do a pretty thorough once over during each oil change.

 

[seanb98]

The ignition tumbler is pretty easy to replace on 1995-up, providing you have a key that works as you need to turn it to get it out. You have to remove the column plastics; start by carefully prying the bezel off the ignition switch. Then there are some torx screws recessed into the lower one. It hinges away from the upper, and then there's some external torx screws going in underneath the top one; if you don't have any e-torx bits you can usually get away with a small socket on those as they aren't that tight. Now you've exposed the column casting itself and you'll see a small hole above where the tumbler sits inside. Disconnect battery, turn key slowly until you see a tab appear in the hole. Press it with a pick and pull the tumbler out.

You must be registered for see images attach

As mentioned earlier 1998 is first year for Passlock antitheft on these trucks; you need to get a tumbler for a 1998 as earlier years will not work. It has the resistor in the tumbler itself for the antitheft, as opposed to it being in the key like earlier VATS antitheft some may be familiar with from Corvettes, Camaros, etc. from years past (on those you can see the "chip" in the key.) You'll need to do a security relearn procedure since the resistor is likely different in the new tumbler. Try to start the truck, it should stall out immediately and flash the "security" light. Turn key off. Now this next part repeat three times: Turn it back to "on" but do not start it. Let it sit 10 minutes. That should do it...it's been years since I've done one so you may want to 'net search that one for accuracy.

Distributor gear is problematic on *some* of the Vortec engines as they were improperly hardened from the factory. I agree with the "ain't broke, don't fix it" mentality on these as you need a good scan tool to properly set the timing once you've pulled the distributor on one of these engines; you cannot do it with a timing light.

Lastly from what I saw in your original post. Limited slip additive is a no-no. If you've got RPO code G80 on the option label in your glovebox, this is a locker (Eaton Gov-loc) - it is not a limited slip or posi; those were not offered in these trucks. Per GM service bulletin you should not use any limited slip or posi additives as they can cause the Gov-loc to not work properly.

Richard

Thank you for all the helpful info! I'll definitely be replacing the ignition lock cylinder, it sounds pretty easy.

It does look like I have the G80 option. So, is it really going to hurt anything having the limited slip additive in there, or is just recommended not to use it because it decreases the lockers ability to function as designed? I don't really care if the locker properly functions or not as long as it isn't going to cause any damage having the additive in there.

Would be kind of interesting to know what all those other codes are.

You must be registered for see images attach

 

[tinfoil_hat]

Sounds like I'll definitely be doing those gaskets. Can't be too bad of a job.

I did not open the block drains, I was not aware that there were any. Where are they? I did run the heater full blast both front and rear between each flush with a fill of clean water, and drove around for a bit each time. Thermostat was removed so water would constantly circulate. Repeated this around 6 times before getting mostly clean water out of the radiator drain.

The block has two drain plugs located about mid engine, just above the oil pan flange. On the passenger side the plug is also the knock sensor. On the driver side it's a hex head bolt about 9/16ths. Both are male pipe fitting tapered threads.
If you do the lower intake gaskets, you might consider draining the coolant. You can re use it if you can catch it.
The gaskets are famous for failing but the reason why is up for debate. Common theory holds that Dexcool eats the gaskets. Others call BS. Either way it's a common problem.
You can do it in a weekend if you are handy with a wrench. You need the Felpro gasket kit and a tube of RTV. You unplug most of the harness and lay it over on the driver's side. Then you unbolt the ac compressor and lay it over on the passenger side. Other than that, the hardest part is pulling the distributor. You have to put it back exactly how you found it. There are lots of great videos on Youtube.