My engine is the I5 3.5L.
I checked the differential level and it has oil. I've looked up and down the engine in every possible angle my eyes can see with a powerful flashlight and I still cant see the source of this leak. I am 90% confident the leak is coming from the right side of the engine (the side with the exhaust manifold and coolant reservoir). I've checked the oil filter and both the oil channel thingy and the surrounding area around the filter is clean. I did a bit of research and also checked the solenoid but that also seems to be clean.

When I get some more time I will spray the engine down and see if that makes the source more obvious.

 

The valve cover gasket was replaced about a year ago. Unless you are talking about something else? The shop I just took the vehicle to said that it was not leaking from there and I personally don't see any new or old oil around the top section of the motor. Everything you can see from the open hood is completely clean.

 

I took the vehicle back to the original shop because I was smelling gear oil when I would get out of the car after driving and I never once saw their fluorescent additive (checked with a backlight at night twice). They had their "master technician" take a look at the vehicle and he confirmed my original suspicion that I have a leak in the front differential. Their invoice says replace pinion seal and axel shaft oil seal. They are quoting $1200 parts and labor. I don't think I will ever bother with this shop again.

 

Number 1 cause of diff leaks is ……………. Overfilling.

Parked on a level surface, check the fluid level yourself.

 

I checked this on 3/26/24 and It had oil but from my finger measurement it was about an inch below the fill hole.

 

That would be low.

How many miles on your 3? If it is time, a rebuild would change out the seals with bearings, worn gear/pinion and gasket etc. That would cost more than your quote.

 

Hey Jim, Lucas has some products that may help in certain situations.

If your leak is from a front dif bearing. Check to verify your lift is in spec and not high. High front lift can cause a bearing leak.

Slightly better gear oils can be less likely to break down.

 

I have to estimate because the engine has been changed and my odometer stopped working at 91,000. its been about 6 years since my odometer stopped working so Id say at least 150,000 miles.

 

The whole truck is stock no aftermarket lifts. I know my control arms need to be replaced and my alignment is out of wack.

My shop also let me know that the tires ive been driving on are very different in tread depths. they said the difference was over 6/32.

 

Even a bar lift can throw your bearings off. Front torsion bars can be cranked for a partial lift. The prior owner could have performed this lift in his driveway.