Is this safe for diesels, specifically the Duramax 6.6L?

Yes..... According to Bars Product, this is compatible with all engines and engine oils.

Can you use this with synthetic oils

Yes, I have used it with synthetic oil with no issues.

What it does with my other gasket that has not have a leak?

If I'm understanding your question correctly.... you would like to know what effect this has on gaskets that are not leaking? The answer is nothing..... Thank you Eric

Is this safe to use with other gas additives such as seafoam, lucas?

Yes there is no problem. This gets poured into your oil crankcase not into your gasoline. Seafoam usually gets poured into your gas tank to clean injectors and cylinder walls sometimes you can put it in the crankcase just about 4 oz to clean junk this does not stop any leaks usually done 100 or 200 mi before an oil change. Lucas has many products some that are injector cleaners that go into the fuel tank some that are oil stabilizers or stop leaks or friction additives that go into your oil crankcase you can have Lucas oil additive/stop leak and bars leak in your oil crankcase they don't interfere with one another

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Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

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Low Oil Level?

Product ID: 3673728

Details

Brand
Bar's Leaks
Item Weight
1.1 pounds
Liquid Volume
16.9 fluid
Package Information
Bottle
Recommended Uses For Product
Fleet and

⛽Stops leaks in 100 miles

🔧Works on all engine types

🛠️Easy add-on at oil change

¥4614

Duties & taxes included

In stock

Sold byAmazon JapanDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🛢️ Seal the deal on leaks before they seal your wallet!

TRUSTED LEGACY - Proven formula since 1947, with thousands of satisfied drivers keeping their engines leak-free.
LEAK STOPPING POWER - Seals rear main, cam, and timing cover leaks fast—most stop within 2 days or 100 miles.
SEAL RESTORATION TECH - Restores worn, dried, and hardened seals to like-new condition, preventing costly repairs.
EFFORTLESS APPLICATION - Simply add to your engine oil at oil change—no mechanic needed, no mess.
UNIVERSAL COMPATIBILITY - Formulated for gasoline, diesel, synthetic, and high mileage engines alike.

Bar's Leaks Rear Main Seal Repair is a 16.9 oz liquid additive designed to stop oil leaks from rear main seals, cam seals, and timing covers. Easy to use by adding directly to engine oil at oil changes, it restores worn seals and works on all gasoline and diesel engines, including synthetic and high mileage oils. Most leaks stop within 100 miles or 2 days, offering a fast, affordable alternative to costly repairs.

Specifications

ASIN	B00754T6TK
Best Sellers Rank	#5,857 in Automotive ( See Top 100 in Automotive ) #13 in Fuel Additives
Brand Name	Bar's Leaks
Container Type	Bottle
Customer Reviews	4.2 4.2 out of 5 stars (3,175)
Global Trade Identification Number	00046087010402
Included Components	One bottle Bar's Leaks Rear Main Seal Repair
Item Form	Liquid
Item Type Name	Bar's Leaks Rear Main Seal Repair
Item Weight	1.1 pounds
Liquid Volume	16.9 fluid ounces
Manufacturer	Bar's Leaks
Model Number	1040
Number of Items	1
Part Number	1040
Recommended Uses For Product	Fleet and plant maintenance.
Specific Uses For Product	Fleet and plant maintenance.
UPC	046087010402
Unit Count	16.9 Ounce
Warranty Description	No

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Trustpilot

TrustScore 4.5 | 7,300+ reviews

Suresh K.

Very impressed with the quality and fast delivery. Will shop here again.

4 days ago

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The product exactly matches the description. Very satisfied with my purchase.

5 days ago

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