Under the head - 3400 GM - 304k Miles

[Brent_G]

Doing a LIM and head gaskets in a 04 impala with the 3400 and 304900 on the odo. After pulling the heads was extremely impressed by the condition of the cylinders and had to share. The owner is a customer of ours who runs a taxi service in town - this one sees the longer trips as well as in town. They got the car 30k ago and when I did the first inspection it has a jiffy lube sticker in the window. PO did 5k-7k on quick lube oil

Cylinders have just minor polishing up top where the rings stop and crosshatch the rest of the way down. No ring ridge at all and the rest of the engine just has minor varnish. 3/4 qt burn or so between changes (5-8k). Only issues found was PO or dealership put a ton of stop leak in this thing. Impressed it lasted 30k with how the LIM looked. HG was not leaking externally but cyl 1 failed leak down and was pressurizing the cooling system and LIM was leaking externally.

 

[The_Eric]

People like to bag on the 3.1 and 3.4, but I think they're a heck of an engine. #1 is pretty much the cylinder that fails (head gasket).

 

[CharBaby]

Do you know if this the first gaskets job that is being done on this engine in 305K?

I too always thought that the GM 3.1L/3.4L/3.8L pushrod engines were quite good engines that made good power/torque all day long. Their achilles heel was always their IMG & HG. And like any engine that has a reputation for having issues, it's not every single one that was ever made, just way too many over the years without GM being in too much of a hurry to fix the problems.

 

[pbm]

The 3.1 in my (sold) 02' Buick Century was a great engine.
I routinely got over 30 mpg on trips and it had plenty of power too.
I had the LIM gasket done at about 75K (using the Felpro PS). I sold it with 120K and I'm sure it's still running although the rockers are probably rusted through by now (a weak spot on that era Century).

 

[SwampSurvivor]

At 304000 miles, how much longer does the transmission have left?

Is a 304K mile car worth paying to have a shop do the head gaskets and transmission?

Looks good for its mileage

 

[JHerriot]

The 3.4 in my Alero is at 152k or so and I've just done the gaskets with Fel Pro after discovering coolant in the oil via an analysis (and a slight LIM gasket external leak). Doing a little minor rust repair next month and I think it'll be in good shape for a few more years on the road.

 

[JHerriot]

Originally Posted By: Miller88
At 304000 miles, how much longer does the transmission have left?

Is a 304K mile car worth paying to have a shop do the head gaskets and transmission?

Looks good for its mileage


Like my car, it isn't worth anything really. It simply comes to this point: will it continue to do car things and get you where you want to go? If so and if the body is decent, and you can do some work yourself, the monetary value of the car means nothing. It'll be cheaper to make even these repairs at a shop than to buy anything half decent and you'll have no knowledge of its history as you would the older car.

 

[TomYoung]

Originally Posted By: Miller88
At 304000 miles, how much longer does the transmission have left?

Is a 304K mile car worth paying to have a shop do the head gaskets and transmission?

Looks good for its mileage

It is very cool to see super high mileage engines, but I have to agree with this poster that this teardown may be a little questionable. Was a short block not cheaper, and even if not cheaper, wouldn't it be better if the idea is to reset the clock. If you are doing this work to get another 50k, how does that make sense economically. We are dealing with a taxi service and a very prosaic car. We should live in realityville.

 

[Brent_G]

LIM has definitely been done before.

Trans has been rebuilt once - fluid is good in it and shifts fine. The body is immaculate for its age and the car drives great.

Agreed it is a bit questionable at this mileage to put this kind of time and money into it - however, we just use this work for filler - we are a semi shop - thus the labor rate is discounted for him which helps.

 

[Schmoe]

Like the way the oil viscosity, amount and drain nut size is well written in front.

 

[turboseize]

Originally Posted By: JHerriot
Originally Posted By: Miller88
At 304000 miles, how much longer does the transmission have left?

Is a 304K mile car worth paying to have a shop do the head gaskets and transmission?

Looks good for its mileage


Like my car, it isn't worth anything really. It simply comes to this point: will it continue to do car things and get you where you want to go? If so and if the body is decent, and you can do some work yourself, the monetary value of the car means nothing. It'll be cheaper to make even these repairs at a shop than to buy anything half decent and you'll have no knowledge of its history as you would the older car.


+1


It is almost always cheaper to repair a somewhat decently maintained car, even when the repair bill exceeds the "value" of the car, than buying a replacement.
That is because you will not be able to adequately replace a maintained car for the little money it might have as market value. As a rule of thumb, any used car will have some issues. In the best case, the seller wants to get rid of it before the next service is due, but more often than not there are some hidden faults (which the seller might know or not), which you will have to find and repair eventually. From my experience, it is prudent to calculate with an additional ~2000€ to 2500€ repair bills that any 10+ year old used car will produce within the first 12 months of purchase. Add that on the market price. But first, you'd have to find a replacement. Depending on the car, that might be easy and quick or not. For example, if I were to find a good pre-facelift Saab 9000 turbo in Germany, I'd have to search a few months, I'd probably have to drive several hundred km several times to have a look at cars that are not nearly half as good as advertised, and then finally I might find a car 600km away. How much does all that driving cost? And what is your time worth? And then there are the actual transaction cost: buy new license plates and have the car registered (the next 100€ go out of the window).
If you add all this together, you can replace engine and gearbox and the entire suspension before you reach the true cost of buying a replacement.

So yes, pouring money into an old high-mileage car without any "market value" can make a lot of sense, economically.

 

[ARB1977]

Impressive

 

[tig1]

Originally Posted By: JHerriot
Originally Posted By: Miller88
At 304000 miles, how much longer does the transmission have left?

Is a 304K mile car worth paying to have a shop do the head gaskets and transmission?

Looks good for its mileage


Like my car, it isn't worth anything really. It simply comes to this point: will it continue to do car things and get you where you want to go? If so and if the body is decent, and you can do some work yourself, the monetary value of the car means nothing. It'll be cheaper to make even these repairs at a shop than to buy anything half decent and you'll have no knowledge of its history as you would the older car.


+1. For the most part it's cheaper to fix em, than buy em.