What can I do to tell if my HG is really getting ready to go? Im losing coolant somewhere and my oil cap is milky but the Toyota dealership is telling me that they are confident its not a head gasket.. They put die in the cooling system and run the truck for a while over 2 days and cant find a leak. Every 1000 miles or so my overflow bottle is empty and I can smell it, its starting to miss and run a little rough and with the milky cap, in my opinion its doing exactly what it did before the HG let go last year. Other than a compression test what can you do to diagnose a possible head gasket failure? Im picking the truck up in the morning and am seriously thinking about paying annother mechanic to do some tests so If it is a HG I can go above the service crew at the dealership that are telling me its OK. Any input would be great! ~Matt

 

Leak down test

 

x2 on the leakdown test and don't run the motor another minute with water in the oil - your bearings may already be damaged but if not it doesn't take long.

http://web.archive.org/web/200712121...s/leakdown.htm

 

Did you tell them that it's leaking internally, most likely into the exhaust or leaking exhaust gases into the coolant possibly? I would lean more towards exhaust gases pushing the coolant out since you said you can smell it and it needs to be topped off.

The most important thing that you need is DOCUMENTATION, go to another mechanic and have them perform a leak down test and print you out a diagnosis. It sounds like Toyota isn't going to make this easy on you but if you come prepared you should be fine. Just remember, that dealer is not your friend but your enemy! You must be tactful here.

 

Im picking it up now and dropping it off at the mechanic that Ive used since I was 16 for everything other than the truck to have a leakdown test done, the dealership just had the nerve to tell me that it could still have bubbles in the system and thats where the coolant is going.. Really?? Really??? I asked, I even said so your telling me that it holds around 8 gallons of coolant in a 3.0.... Then I said Ill be there in a few to take it for a real diagnostic! ~Matt