Want to Blow you Transmission? Don't replace your rad....

[BlazerLT]

Yip, just got back from a glorious $3100 bill from the tranny shop for a rebuild including a new rad etc...

The transmission was shot, but even better than that, so was my rad and I never saw it coming.

Coolant got into the tranny cooler and over time took the clutches out, scored my valve body plate and leached the plastic out of the solenoids. The solenoids were soft. Malleable. Scary.

The tranny guy was straight out astonished as to how I got 140,000 miles out of the tranny???!!!

He said he normally changes them out after 100,000 or less for the 4L60E and he said that even with no coolant I was lucky to get that kind of mileage out of it. And I was......

So guys, just as a kicker, I want to put this bug in your ear. The Blazer rad is only good for about 10-11 years before it will start to fail even in a perfect scenario. This is referenced by 6 shops I talked too and for $200, it is cheap maintenance seeing your coolant, your oil and your tranny all go through it.

My truck is pristine and it went on me and ended up cost me bigtime. Take my word for it, just swap it out, hell, you can probably get a rad cheaper than me.

This is the achilles heel of this truck, it goes and the whole truck goes.

I had coolant in the oil as well in my PCV catchcan.

My poor baby deserves better.

HOLY FAWK IT RUNS GREAT NOW THOUGH!!!!!

[DINO55]

Hey BLT

Would regular flushing's of the (COOLING SYSTEM) prevented this from happening??? like every two years?

[BlazerLT]

From what I have done, no, it won't.

It will break down regardless and compared to the possible engine damage and the tranny loss from my point of view, just swap in a new one, so easy to do as well.

Should take not longer than a couple of hours or so.

[Teal95Jimmy]

Is there a way to tell the internals on the rad are on their way out, other than a complete failure of something else like your tranny

[chcknugget]

This is all true, Thanks BLT

[SComp23]

Man that sucks, as well as the fact that the guy basically said that it is routine maintenance to switch out a tranny at 100k

[BlazerLT]

The 4L60E isn't exactly a robust tranny. The 1994 and 1995 are fine, but from what they said, 1996 up are a lot weaker.

There is no real way to see if you rad is leaking coolant into the oil or tranny unless you inspect them both.

I caught it getting into the oil through a small amount collecting in the PCV catch can I had installed.

The catch can right there saved me 1000s.

I just wouldn't take the risk with our all in one setup.

[ZL1power69]

Originally Posted by BlazerLT

The 4L60E isn't exactly a robust tranny. The 1994 and 1995 are fine, but from what they said, 1996 up are a lot weaker.

There is no real way to see if you rad is leaking coolant into the oil or tranny unless you inspect them both.

I caught it getting into the oil through a small amount collecting in the PCV catch can I had installed.

The catch can right there saved me 1000s.

I just wouldn't take the risk with our all in one setup.

I've wondered lately if my rad is failing. heres an example; i took about a 20 mile drive yesterday (10 miles each way). as u know, when the thermostat opens the temp gage drops from about 220 to 190. well, after that happened, i noticed that the temp went back up to 220 and then back down to 190. this happened twice during the trip. i get home and decide to check the coolant (after letting it sit). i removed the rad cap and i couldn't see any coolant. it took about a 1/4 of a jug of coolant to replenish the rad. I don't see any visible leaks in the rad itself, the overflow level stays the same, and i don't see any coolant in my pcv catch can. any suggestions?

[wolfox]

My Rad went the same time my water pump went and my lower intake fiasco months back. The crimps and seals around the plastic end tanks where they mate to the aluminum rad core leaked like a seive so it was replaced, right on the 11 year mark @ about 144K miles. The radiator and pump were definitely cheaper than a tranny fix or an overheated engine block, totalling $320 for OEM rad and coolant pump at a GM parts discount store in town.

[s10blazerman4x4]

Mine took out a fresh v8 and not the trans.

[BlazerLT]

Originally Posted by ZL1power69

I've wondered lately if my rad is failing. heres an example; i took about a 20 mile drive yesterday (10 miles each way). as u know, when the thermostat opens the temp gage drops from about 220 to 190. well, after that happened, i noticed that the temp went back up to 220 and then back down to 190. this happened twice during the trip. i get home and decide to check the coolant (after letting it sit). i removed the rad cap and i couldn't see any coolant. it took about a 1/4 of a jug of coolant to replenish the rad. I don't see any visible leaks in the rad itself, the overflow level stays the same, and i don't see any coolant in my pcv catch can. any suggestions?

Yes, you need to replace your rad cap. The stock unit is flawed and won't seal properly which therefore won't hold the 15-16psi needed for the cooling system.

This will allow the coolant to boil off a bit.

Get the vehicle on ramps, start the engine cold with the rad cap off and the heater on full hot and max fan and start adding coolant as the level starts to drop. This will have the rad set as the highest point in the cooling system and therefore air will slowly migrate to that point instead of in your heater core coolant lines.

Once the coolant starts to rise in the rad and start to come out, install the new rad cap and fill the overflow tank to about 3/4s.

With Dexcool, they say to keep the overflow tank topped up and just below the overflow hose line.

Take it for a drive and get it warmed up and then come back and turn the heater to full cool and you might burp some coolant but that is good and means you have all the air out.

[ZL1power69]

Originally Posted by BlazerLT

Yes, you need to replace your rad cap. The stock unit is flawed and won't seal properly which therefore won't hold the 15-16psi needed for the cooling system.

This will allow the coolant to boil off a bit.

Get the vehicle on ramps, start the engine cold with the rad cap off and the heater on full hot and max fan and start adding coolant as the level starts to drop. This will have the rad set as the highest point in the cooling system and therefore air will slowly migrate to that point instead of in your heater core coolant lines.

Once the coolant starts to rise in the rad and start to come out, install the new rad cap and fill the overflow tank to about 3/4s.

With Dexcool, they say to keep the overflow tank topped up and just below the overflow hose line.

Take it for a drive and get it warmed up and then come back and turn the heater to full cool and you might burp some coolant but that is good and means you have all the air out.

i do not recall what lb cap is on the rad but i know for a fact that it is not the stock one. also, i have done the procedure u listed 3 times already and there is still some air in the system (everytime i have to refill the rad, air bubbles to the top of it). i have not touched the overflow in about 3 months because it stays at the same level all the time.

[blazee]

That's most likely your problem, either the line going to the reservoir is clogged, or your radiator cap isn't sealing properly.

[joeuser742]

That's scary. I'll have to make sure and keep an eye on mine, or replace the radiator because the trans was rebuilt just before I got the truck. I already had the trans out to replace the rear seal, I don't want to do that again. Thanks for the info.

[Ultrashock]

Luckily my tranny was already rebuilt when i bought it......

My radiator blew up on me anyway a few months and it cost me 500 dollars to have it replaced and installed. It cracked right below where the cap is...