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FREE 30-day refund/replacement
To qualify for a full refund, items must be returned in their original, unused condition. If an item is returned in a used, damaged, or materially different state, you may be granted a partial refund.
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Availability:
In Stock.
Arrives
Thursday, May 14
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Size: 1 Quart (32 Ounces)
Features
- FULLY-SYNTHETIC FORMULAS - created from polyol ester base stocks, offer excellent lubrication under extreme conditions
- ENGINEERED TO PROVIDE - the highest degree of protection and improvement of differential efficiency for better mileage, longer drain intervals, and less wear, exceed API GL-5 specifications
- NOT RECOMMENDED - for most synchro applications due to the product's extreme slipperiness
- POPULAR GEAR OIL FOR - Many performance racing applications like Sprint, Midget, Dirt Late Model and Quick Change Differentials, Detroit Lockers and spools, NHRA Top Fuel and Funny Car rear ends, most popular ShockProof product, many racing and specialty applications
- WHY RED LINE - Established in 1979, Red Line Products perform & protect better than any on the market. No compromises
Material: Synthetic
Brand: Red Line
Package Information: Bottle
Liquid Volume: 32 Fluid Ounces
Item Weight: 1.7 Pounds
Brand Name: Red Line
Recommended Uses For Product: Gear Oil
Specific Uses For Product: Racing transmissions and transaxles, high load conditions, high-performance differentials
Item Form: Oil
Global Trade Identification Number: 49
Manufacturer: Red Line
UPC: 083522582049 083522582094
Item Type Name: Engine & Oil
Included Components: Red Line 58204 Heavy ShockProof Gear Oil - 1 Quart Bottle
Unit Count: 32.0 Fluid Ounces
Warranty Description: Limited Manufacturer
Container Type: Bottle
Liquid Volume: 32 Fluid Ounces
Item Weight: 1.7 Pounds
Material: Synthetic
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Thursday, May 14
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 1 Quart (32 Ounces)
Red line heavy shockproof gear oil is the best by far for any Harley trans. It will shift like a dream (and you can find neutral) will also quiet down the clunk into gear. Let's be real here, its a Harley with a chain drive primary and its; going to clunk. If your one of th0se who hates the clunk, buy a Honda.
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Reviewed in the United States on January 24, 2025 by jfaunce
Size: 1 Quart (32 Ounces)
25 minutes of hot laps is a ton of abuse on a "stock" 8.8" solid axle rear diff. And I do 4 or 5 sessions a day. It's a lot of heat! I do have a breather which helps immensely but not a diff cooler. The Red Line Heavyweight oil gives you industrial level protection but flows like a lighter oil. My axle calls for 90w140, and the Heavyweight Shockproof oil flows great and has held up better than any other fluid including Red Line "yellow" 90w140 gear oil, or Royal Purple synthetic heavy duty. If your application is high heat for long periods of time, this product is amazing!
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Reviewed in the United States on December 20, 2018 by Spencer T.
Size: 1 Quart (32 Ounces)
Great product. Notably quieted and smoother shiftng. Expensive though.
Reviewed in the United States on October 15, 2023 by Frankie-g
Size: 1 Quart (32 Ounces)
I am writing this review for the nay-sayers of this product. I have owned Harleys my entire life and Harley transmission have some noise issues going into 1st gear. This oil will stop that and the transmission will shift smoother than it ever has. Years ago I took my motorcycle into the shop for fluid change. I got home from the shop, which was around 70 miles and noticed the transmission was shifting differently. I checked the transmission oil and none was in it. They forgot to fill it up. The Red-line oil is so thick that it coated the gears and bearings and protected them from damage. If this would of been any normal oil. The bearings would of been damaged and the transmission would of needed rebuilded or even replaced. This oil saved me a minimum of 1,500 to a maximum of 8,000. I swear by this oil and will not run any other.
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Reviewed in the United States on September 11, 2023 by Dave G.
Size: 1 Quart (32 Ounces)
Best transmission oil for a Harley
Reviewed in the United States on October 12, 2024 by Daniel G. Daniel G.
Size: 1 Quart (32 Ounces)
Harley Recently modified their recommendation for transmission fluid to gear lube from the previous syn3 motor oil or their trans specific fluid, and they now offer a gear lube weight oil. People have been using redline in their transmission long before harley changed their suggestion though. Ive personally ran this in my own motorcycle, but I did not continue to use this because IMO it didnt work as well as amsoil has for my bike, but that doesnt mean I wouldnt recommend this fluid its much better than anything HD has to offer in terms of protection.
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Reviewed in the United States on October 29, 2022 by Vicious cycles
Size: 1 Quart (32 Ounces)
Used this in my 1999 Subaru Impreza Outback Sport with noisy front and rear differentials. I threw some mobil0-1 75w-90 in each diff for about 1k miles to rinse things out. Just dropping the beat-up, dark diff fluid and going to Mobil 1 was a marked improvement alone. After running that sacrificial fluid for 1k miles, I drained it (and it was in much better shape, but still appeared QUITE DIRTY) and installed some Lucas full synthetic 75w-90 gear oil with about a half of the Heavy Shockproof quart going into the front and a half going into the rear diff. I put the Redline in first so it would mix better. Both my front and rear differentials are OPEN (not LSD; if you have an LSD, DO NOT USE this redline shockproof series). Immediately, I noticed that the diffs were notably quieter and that the car even accelerated and coasted more easily than even with the mobil-1 gear oil. I used the heavy shockproof because I'm in Florida and it never gets very cold here (it dips below freezing for a few hours, a few nights of the year, but only just below). If you are not in a southern state (FL, Texas, AZ, NM, LA, etc), I would advise selecting the lightweight shockproof instead. Overall, I'm extremely satisfied. If you have an open diff, or an air locker (anything but an LSD), you owe it to yourself to add a portion of shockproof to your diff. Quieter means cooler. That's always a good thing. Also, NEVER add this to any transmission. Even a manual. Your synchros will be permanently too slippery to work properly.
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Reviewed in the United States on November 1, 2016 by TinkerGuy
Size: 1 Quart (32 Ounces)
A noticeable difference in how loud the transmission is. This is good stuff! Although, I would highly recommend that you let your bike warm up on cold days for at least a few minutes (which you should be doing anyway). A pal has 200,000 plus miles on his Harley and swears by this stuff. I’ll trust his judgment since his bike has the miles to prove it.
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Reviewed in the United States on January 15, 2021 by RDAche RDAche