Why do a head gasket as preventative maintenance? (2 Viewers)

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I have a 1997 80 series with 271k miles on it and to my knowledge, original head gasket. I purchased the truck not long ago with 265k miles. The previous owner had it for a little over a year and did not have any maintenance history prior to him purchasing it. All fluids have been drained and refilled. Radiator replaced. Oil leaks fixed including oil pump, crank seal, valve cover gasket, and distributor. It has a slow leak from the oil pan arch seal. I get an occasional P0401 that I haven't spent much time chasing down yet. Other than that it runs great. Have a recent oil analysis that shows high aluminum but otherwise completely normal. Have yet to do a repeat analysis to see if the high aluminum is consistent. Planning to have it compression tested soon.

My question is, assuming the compression testing is normal, is there any reason to consider a head gasket replacement and rebuild as preventative maintenance? Or just keep driving it until I'm forced to do something? Also how might I be able to tell if the head gasket has been replaced previously since there's no detailed maintenance history prior to the previous owner?

My concern is that I will be using the truck for long trips and may have it in places where it may be impossible to get a tow truck to. I've read a few threads and there doesn't seem to be a general consensus. I would like to wait if its reasonable to do so. I guess what I'm looking for is reassurance, or for enough people to tell me I should so that I change my mind.
 
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A car fax report might show some maintenance history. I think the hg issue was resolved with a better gasket by 1997. Many are over 300k on original hg we just don’t hear these stories nearly as much.

The hg job can be done for under $1k in your own garage and possibly as much as $2500 at a shop if done without short cuts.

The degree of peace of mind it will bring to you is ultimately what will determine if you do it as a precautionary measure.

If your engine has been taken care of decently, 267k is nothing for the bottom end.
 
I have a 1997 80 series with 267k miles on it and to my knowledge, original head gasket. I purchased the truck not long ago with 265k miles. The previous owner had it for a little over a year and did not have any maintenance history prior to him purchasing it. All fluids have been drained and refilled. Radiator replaced. Oil leaks fixed including oil pump, crank seal, valve cover gasket, and distributor. It has a slow leak from the oil pan arch seal. I get an occasional P0401 that I haven't spent much time chasing down yet. Other than that it runs great. Have a recent oil analysis that shows high aluminum but otherwise completely normal. Have yet to do a repeat analysis to see if the high aluminum is consistent. Planning to have it compression tested soon.

My question is, assuming the compression testing is normal, is there any reason to consider a head gasket replacement and rebuild as preventative maintenance? Or just keep driving it until I'm forced to do something? Also how might I be able to tell if the head gasket has been replaced previously since there's no detailed maintenance history prior to the previous owner?

My concern is that I will be using the truck for long trips and may have it in places where it may be impossible to get a tow truck to. I've read a few threads and there doesn't seem to be a general consensus. I would like to wait if its reasonable to do so. I guess what I'm looking for is reassurance, or for enough people to tell me I should so that I change my mind.


Owing to the mileage, uncertainty of present head gasket (original or not) and the possibility of become stranded far from home, yes....I would recommend replacing it.

Mine (1997 model) went 316K miles on the original. Might have gone further except I think I pushed it over the edge when doing an engine flush. So I wasn't actually driving mine when it failed. However it failed in a spot that so many do (number 6 cylinder) so that rather suggests it was on the cusp anyway.

If you plan to keep and enjoy the vehicle for a long time....it might not be a bad thing to consider.
 
just a different perspective, your car, like mine, given age and mileage, has so many things that could break in middle of no where, where tow truck can't come. would you then chase every single one of them? or just stop with HG? (unless HG deserves special treatment..)

I know, not an answer, but just something to consider..
 
just a different perspective, your car, like mine, given age and mileage, has so many things that could break in middle of no where, where tow truck can't come. would you then chase every single one of them? or just stop with HG? (unless HG deserves special treatment..)

I know, not an answer, but just something to consider..

Head Gasket deserves special treatment. Many of the other things that could fail can easily be carried as spares or be fixed readily with parts brought in. Head Gasket is a major task and failure can potentially ruin other parts.

Your point however is well taken (where do you stop). We leave that up to each individual to decide since use of the vehicle, finances and other considerations will vary.

But if you had nothing else on a vehicle you will always want to have a reliable head gasket and good brakes. ;) And maybe a bottle opener.
 
The headgasket discussion is always an interesting one to me. On most other vehicles, headgaskets, main bearings, and everything in between would be toast by 300k. No question. So I think there needs to be a little more perspective when people here say LCs notoriously blow headgaskets. By that metric, every vehicle notoriously blows headgaskets because most don't even make it past 200k without cooling system failures, etc.

I, personally, would never do a headgasket as preventative maintenance. LCs can blow headgaskets when they get hot (like all vehicles). That's not enough reason to tear into something that's working. And if you've been reading on these forums for a bit, you'll see that when people start tearing stuff apart, other things start going wrong too.

If this was an MKIII Supra which had an undertorqued head at the factory, then it'd be a different story. If you want peace of mind, replace the whole cooling system, flush but with no pressure, add a ScanGauge or UltraGauge, and watch the temps. Like you would do on any other car.

But hey, this is, like, just my opinion, man.
 
Also keep in mind a head gasket failure can be a slow process and not always an immediate catastrophic failure that would still allowing driving back to civilization. Proper maintenance of the cooling system is the best of all preventative care to eliminate any overheating issues. Although rare, a second failure of a head gasket is certainly possible. Regular oil analysis may be something you want to invest into. On trail repairs can include leaving radiator cap loose so the cooling system doesn't build pressure or adding a stop leak product to your spare parts and tools you carry.
 
The term "blown headgasket" makes it sound like either the gasket is fine, or suffers a major failure. I believe that many high milage 1FZ engines with the original gasket will show minor leakage if tested carefully. The minor leakage grows steadily over the heat cycling of the engine. When the leakage if enough to force the water out of the cooling jacket and the engine overheats and destroys the head gasket by over compressing it, that's where we get the phrase "blown headgasket". The aluminum head expanding more than the iron block produces a micro scrubbing motion that damages the armor of the gasket around the combustion openings, the motion is greatest at cyls 1 and 6. The cost and complication of replacing a head gasket on these engines makes many people question the point. If it was cheap and easy to do, there wouldn't be so much hesitation. I personally think its worth it if you want the engine to continue to be reliable.
 
For the time being, get your coolant system up to par. After a new radiator and fan clutch my engine rarely goes over 195F even in the mountains. Gives me peace of mind on the original HG.
 
I plan on keeping my cruiser till i die. Mine is using oil at a rate of 1 quart every 3 or 4 tanks of gas. I am going to go ahead and do a top end rebuild that should last me the rest of my life. I have 225k on my truck and don't see putting another 200k on it.
 
I know you started this thread to try to answer this question, but you're just going to get a bunch of varying opinions.

I too worry over this question. I bought my truck with 300k and a shady past. I've put around 40k on it (some of that time turbocharged) and I know I've overheated enough to shut down the A/C at least twice. I've finally got my cooling system working great after several years of poor cooling performance. I still haven't blown my head gasket, and I may never do so, but I do worry about it. I will say 90% of that worry comes from our yearly trip to Yellowstone where I am in the middle of bumblefork Wyoming towing a camper with my wife who is already skeptical of my life decisions. If it wasn't for that type of road trip, I wouldn't sweat it at all.
 
I know you started this thread to try to answer this question, but you're just going to get a bunch of varying opinions.

I too worry over this question. I bought my truck with 300k and a shady past. I've put around 40k on it (some of that time turbocharged) and I know I've overheated enough to shut down the A/C at least twice. I've finally got my cooling system working great after several years of poor cooling performance. I still haven't blown my head gasket, and I may never do so, but I do worry about it. I will say 90% of that worry comes from our yearly trip to Yellowstone where I am in the middle of bumblefork Wyoming towing a camper with my wife who is already skeptical of my life decisions. If it wasn't for that type of road trip, I wouldn't sweat it at all.
I'm sure there's fine repair shop in Rawlins or Rock Springs, hope you never have to find it.

On subject, my 1997 has 216 on clock and I'm not planning to replace the HG unless I see signs of trouble. Hoses, belts, T-Stat and fan clutch have been replaced, system cleaned with Thermocure, rinsed with distilled, filled with Red. Radiator still looks solid (no discoloration of the plastic top) so I left it in service. I'm consuming roughly 1/2 a quart of oil every 5 thousand miles, a little of that is a slow leak off the upper pan. I've read the pros and cons and am pushing forward as is.
 
These engines are bullet proof with some basic maintenance., and HG seems to be the one thing that goes without warning and no solid root cause (i.e overheating). Also seems like right around 200k miles most folks see failures. I baby my LC and everything up to par (cooling system, compression, oil, ect), and one day out of the blue I got white smoke. Luckily I was close to home. I did all the work myself but it is quite involved and time consuming.

I look for my LC to be reliable. Peace of mind is a big deal to me, and if I hadn't had the failure this is something I would have done as PM.
 
In my case I did the HG as PM for the following reasons:
  • Unknown but clearly poor maintenance history of my 80. Had a new radiator but plenty of crud in cooling system leading me to believe it could have been run hot previously.
  • Leaky valve seals that needed to be replaced to lower oil consumption.
  • All original coolant, vacuum and seal rubber that all needed to be replaced from valve cover to oil pump, etc. Power steering pump also leaked really bad and there were intake side leaks, etc.
  • Curiosity about how the engine looked internally given how rough it was where I could easily inspect.
  • I knew I was going to be traveling far in the 80 with young kids and wife on board. Managing young kids is hard enough without being stuck somewhere unexpectedly, tow truck or not.
An 80 in rough shape benefits from a thorough going over and doing the HG doesn't add that much if you have to do all of the typical baselining items under the hood. If your truck is on the nicer end of the spectrum, doesn't consume much oil and has likely never been overheated I wouldn't feel a need to pull the head.
 
Mine is a 97. Very well maintained. At 260k miles, I noticed a slight miss and a momentary hesitation upon startup one day. Not hugely noticeable, but it did feel abnormal. I commuted daily almost a hundred miles round trip. Drove fine for the whole run home. Ran fine for the next several days. Didn’t think much of it. I have an ultra gauge, so watched the temps like a hawk. Zero cooling issues. About a week later, I went to start my truck while it was in a low clearance underground parking garage. The engine was fully frozen. Turned out I hydro locked #6. HG breached on the fire ring.

To each their own, but I’m of the opinion that past 250k miles, you’re living on borrowed time. But really, to expect a HG to last more that 250k miles seems ambitions. Everything has a service life. 250k miles seems pretty reasonable to me.
 
Also, considering to do HG as PM has a very dangerous side effect, on the same light of thoughts, then it would also force me to consider what PM I need to on my body (exercise, eat healthy etc.) so I don't have a heart attack or a stroke where an ambulance can't reach.. and I with that thought, I stopped further considerations on the HG. lol
 
The bottom end is stout in these rigs but you start getting up there and the head could use a refresh and with as many cases of blown hgs there are I think its more likely than not to surface - at some point.

My 97 blew about 2 weeks into owning it. When I bought it, it was dark and so I dipped my finger into the rad and found liquid and called it good. Checking into it in the following days I found it was straight water and very rusty. Having flushed copious amounts of rust out of the system and replacing with fresh coolant I must have let loose whatever was left of the HG. Upon pulling the head I found itd been leaking into the cylinder for a long time and they just let it use coolant and replaced with water - to the point #6 cylinder wall was pitted. Rebuilt a spare engine and swapped the whole thing out, and of course replaced a lot of other components along the way.

Not worried about blowing a HG and dealing with the associated troubles of that? Run it!

Don’t want to deal with the headache of blowing a HG in a less than desirable place? Replace it

Like the idea of freshening up a lot of other components and having a freshened up engine ready for a second life? Replace it
 

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