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Main seal oil leak

My 98 Camry (181,125 miles) was recently diagnosed having an oil leak located in the main seal. Common problem? How do you manage this. My mechanic said live with the problem, check oil level weekly, use cat litter on the garage floor to collect the oil. OR, a new engine! He did not recommend this.

With a main seal leak the PCV valve should always be inspected and replaced if necessary as a first step. A rear main seal is often the first thing to leak when a PCV becomes clogged.

However, at 181k miles and 11 years of age it’s also quite possible the rubber has hardened and/or the seal has worn a groove into the crankshaft surface where the seal rides. A leaking rear main does not automatically mean a new engine.

If the seal is known to be the problem it’s either live with it or drop the transmission and replace the seal itself, while also inspecting the crank surface at the same time. Odds are the crank surface is serviceable and won’t be a problem.
If this is done and the car has an automatic transmission the front pump seal in the transmission should be replaced at the same time. That’s a given.

What you might consider is having a transmission shop perform this job. The full time transmission guys can whip that transmission out pretty quickly, replace both seals, and have it back together in half a day. Odds are that a transmission shop labor charge would be considerably less than a general repair shop.
I recommended this procedure over the phone to a relative who was having a similar problem and the labor was something like 200 dollars if I remember correctly. Add 20 bucks for a pair of seals and voila.
Hope that helps.

New engine? Why? All it needs is a new seal. This is not necessarily “common,” but at this mileage a leak or two is to be expected. The engine and transmission have to be separated to repair this, and that won’t be cheap, but I do NOT understand why your mechanic says you need a new engine.

Sounds to me like he doesn’t want to tackle this job, and is trying to frighten you our of having it repaired. Find another mechanic.

A new seal will temporarily slow the leakage. Thicker oil will do the job if your engine can handle it. I like to use straight 30 wt to slow the leakage. Usually with 181,000 miles, it’s low risk.

You could also use ‘high-mileage’ oil with the next oil change. This oil has modifiers that will soften and swell those 10-year-old seals, and can slow or stop the leak. It is a band-aid cure, but much cheaper than the alternative of pulling the transmission to replace it. Worth a try, in my book.

You can also try one of the engine seal stop-leak products, like Barr’s Rear Main Seal Stop Leak or a Lucas product. I would use a product only long enough for you to find a reasonably-priced and knowledgeable mechanic that will change out your existing main seal without having to yank the engine. He/she will have to either yank the tranny or at least separate the tranny from the engine to get to the seal. There are ways to carefully R&R the seal but should be done by an experienced mechanic. The Barr’s Seal Leak has worked well in my rebuilt Chevy I-6 cyl. 250 c.i. (46K on the rebuild) for about 20K miles now. A Lucas rear differential sealer product has been used successfully in my A.C. WD-45 tractor final drive and rear diff. assemblies for years now without fault. If you have less than 1K miles on your present oil/filter, I’d just check the oil level, remove some engine oil to make room for that quart of sealer, and dump some right into the engine oil fill cap. If you’re close to oil change time, just wait 'til you do your next oil change and dump a can of sealer in then. I would always stick with the oil type/viscosity recommendations of the vehicle manufacturer for the ambient conditions for the Spring/Summer/Autumn.

Main seal leak does not necessarily mean rear main seal. The front main seal, located behind the timing gear on the crankshaft is the more likely culprit. This car should be due for a new timing belt anyway and that would be the best time to replace it, in the mean time, check oil weekly, use cat litter (clay, non clumping). Should do the cam front seal when the crank seal is done as well.

This is a common problem with FWD cars. The crank seal is right in front of the oil pump.

temp fix,go to work and fix the prob,as long as that is the prob,

DIAG, first ,works the best,