t can only get worse. But hope for the best. I think you're doing the right thing. Because it's a transverse mounted engine - it's a royal pain to replace. If it happened on my 05 4runner - I would fix it the next free weekend. Much easier job, although it is complicated.

 

If it’s not dripping on the driveway I wouldn’t worry about it. Most engines leak a little with age. The amount of oil you’re seeing isn’t going to effect oil level. Unless you are just barely out of powertrain warranty and can convince Toyota to fix it I’d leave it alone.

 

Agree with wolfe. Most older engines will seep a little bit, totally normal and nothing to be concerned about. As long as the dipstick level isn't dropping and it's not leaving drops on your driveway/garage, leave it alone for now.

How many miles do you have on it? Either way, I think you're probably passed the 5 year powertrain warranty window by now.

 

I had this same issue on my ‘16 HL back in September. I was just out of power train warranty. I called the corporate Toyota customer care line and explained the situation. They were very kind and agreed to do what they could to help. I was instructed to take it to my local Toyota dealer for diagnosis/estimate and then call back. Dealer confirmed it was leaking at the timing cover. I gave the service advisor my case number from the corporate call. He took care of the rest. By the end of the day, the service advisor called with the estimate, but then said it will be covered as “customer good-will”. This was on a Friday. He told me it would probably be Tuesday before it was done, as it was a lengthy repair. However, he called on Monday morning and said it was done.
I agree that seepage is “normal” as engines age, but a timing cover leak shouldn’t happen that early. My understanding is that the gasket is a “form-in-place” type gasket, rather than a true one-piece gasket. Rather the FIP gasket is applied as a liquid by a robot at the factory. The issue is that the gasket isn’t always consistently applied for various reasons, thus the leak develops.

 

I had this same issue on my ‘16 HL back in September. I was just out of power train warranty. I called the corporate Toyota customer care line and explained the situation. They were very kind and agreed to do what they could to help. I was instructed to take it to my local Toyota dealer for diagnosis/estimate and then call back. Dealer confirmed it was leaking at the timing cover. I gave the service advisor my case number from the corporate call. He took care of the rest. By the end of the day, the service advisor called with the estimate, but then said it will be covered as “customer good-will”. This was on a Friday. He told me it would probably be Tuesday before it was done, as it was a lengthy repair. However, he called on Monday morning and said it was done.
I agree that seepage is “normal” as engines age, but a timing cover leak shouldn’t happen that early. My understanding is that the gasket is a “form-in-place” type gasket, rather than a true one-piece gasket. Rather the FIP gasket is applied as a liquid by a robot at the factory. The issue is that the gasket isn’t always consistently applied for various reasons, thus the leak develops.

How many miles did you have at the time? In my head, when I made my comment, I (perhaps incorrectly) assumed that OP's Highlander was probably high mileage for this problem to develop. I agree, it's not normal if the mileage is low and the car is only a few years old.

 

This issue goes way back to 2005. My 2005 Avalon also had a slow timing cover leak. Fortunately, it never developed into a bigger leak.

 

Just a quick follow up. My car was purchased new in 11/2014 as a 2015 model year. Pre-covid we were averaging 14k miles/yr. If I had pulled the passenger front wheel off while it was still under powertrain warranty I would have brought it in as I'm now fairly certain (in retrospect) that it had to be leaking well before the powertrain warranty expired.

Given that it's been leaking this long without increasing to the point of dripping on the ground and without coating any of the belts I'm planning on just riding it out.

Next time I have the wheel off and the car is being driven regularly again in the post-COVID19 world I'll clean everything off and see how much it re-spreads during one oil change length.

 

Good plan. With 70K+ miles and almost 7 years old, I don't know that Toyota would be willing to help.

 

New owner of 2019 LE model, purchase this October with 44 000 KM from a Kia dealer in canada. Through an incredible stroke of luck I found the original owner when shopping for used winter tires in a local add. I got original paperwork for the car and all the previous service records. I timing cover leak was identified in september 2020.
When I has the car inspected by an independent mechanic the leak was not very visible, at least not to my eyes.
After becoming the owner I contact the original dealership that looked after the car and they proceed to replace redo the gasket.
The car was at the dealer for a few days, the entire engine and transmission had to come out. They also replace 3 of the 4 shocks which were leaking. That was a surprise given the low milage of the car 27K miles.

 

New owner of 2019 LE model, purchase this October with 44 000 KM from a Kia dealer in canada. Through an incredible stroke of luck I found the original owner when shopping for used winter tires in a local add. I got original paperwork for the car and all the previous service records. I timing cover leak was identified in september 2020.
When I has the car inspected by an independent mechanic the leak was not very visible, at least not to my eyes.
After becoming the owner I contact the original dealership that looked after the car and they proceed to replace redo the gasket.
The car was at the dealer for a few days, the entire engine and transmission had to come out. They also replace 3 of the 4 shocks which were leaking. That was a surprise given the low milage of the car 27K miles.

 

I am joining this club. Took my 2015 HL LE AWD in for an oil change and overall check as I am at 99K and all warranties (CPO and extended) expire at 100K. Fortunately the repair is covered under the CPO Warranty. I had not noticed any leak and was shocked to find what the repair involves.

 

I had not noticed any leak and was shocked to find what the repair involves.

Timing chain repairs are far more complicated then a timing belt because now you to deal with oil (gaskets). A timing belt is a dry system. Also many vehicles the oil pan is bolted to the lower timing chain cover. It gets real involved. Plus the fact it's a transverse mounted engine that makes for tight working quarters.

 

Who thought that design was a good idea? I guess it wasn't supposed to fail.

 

Who thought that design was a good idea? I guess it wasn't supposed to fail.

That design goes back many decades. In general timing chains should last the life of a vehicle as long as you keep up with oil changes.

 

Has any one tried any improvised repairs such as duck tape (LOL) or a sealant on the outside.

 

I was told to bring in to a dealer and pay $165 for a diagnostic. Does that sound right?

 

Is your car out of warranty?