Genuine Ford Fluid XL-3 Friction Modifier Additive - 4 oz.

Bought this during a 1 a.m. diff-fluid rabbit hole for my older Ford daily. Manual says to add friction modifier for the limited slip, so I tossed this XL-3 in with fresh gear oil when I did the driveway fluid change. The chatter on low speed turns calmed down a lot, which was nice. Still get a tiny bit of noise when backing out of my steep driveway, so it is not magic. The little nozzle makes it easy to squeeze into the fill hole without a funnel, which I appreciated. Price feels a bit high for 4 oz, but it beats guessing with generic stuff.

I have a 2000 ford E350 ambulance with a 7.3 powerstroke diesel engine. 3 yrs ago I had to have the rear differential clutch pack replaced. I think he replaced the gears as well. He told me it will chatter a bit but would go away. It did chatter a bit but didn't go away. Recently it has gotten worse so I ordered 2x4oz. bottles of this stuff. It came in 2 separate boxes. I did order them alone due to other reviewers' warning about the smell and they weren't kidding. I also ordered a.big fluid syringe to "inject" it into the pumpkin. I have a prosthetic leg and some back issues due to a disc replacement surgery. This makes it hard for me to get under the truck so I took it to my friends shop. He had one of his young guys do the job for me. I won't lie, I also didn't want to touch the stuff. It stinks. Bad. The whole garage smelled of the stuff even still packed in the boxes. I put it in the side compartment of my van to bring it to the shop. I felt bad, the guy got it all over his hands and i.know it's going to be hard to get off. I hope he is allowed to sleep in the house tonight! Anyway by the time I got home the chatter seems to be.gone. I will have to do some serious sharp turns and reversing on an incline to know for sure, but it already is better doing normal driving with normal turns. I put 8 oz. In because that is what I saw as a recommendation for my differential. Anyway it's good stuff but it stinks. I left the syringe and boxes and empty bottles for him to dispose of!!

Cheaper than box store. Used in my Ford limited slip differential. No chattering from the clutch pack.

I used this genuine Ford XL-3 friction modifier during the rear differential fluid change on my F150 with limited-slip axle. This 4oz bottle is exactly the OEM additive specified in the service manual. Before adding it, I heard annoying chatter while turning at low speeds. After mixing XL-3 with new differential fluid, the noise completely went away. It optimizes clutch friction inside the LSD and protects internal parts from excessive wear. The bottle has a tapered spout for clean pouring with no spills. This factory additive is a must, generic substitutes cannot match its performance. The product arrived sealed and leak-free. If you own a Ford with limited-slip differential, don’t skip this additive during service. It keeps the axle running smoothly.

I own a Ford F-150 and started hearing annoying chatter from the rear limited-slip differential when taking slow turns around my neighborhood. My mechanic said I needed genuine Ford XL-3 friction modifier during the diff fluid change. This 4 oz bottle is exactly what the factory manual recommends. I poured it in while replacing the rear axle oil, and that irritating chatter faded away completely. Now low-speed cornering is quiet and smooth again. The bottle arrived sealed without any leaks. I always stick to OEM fluids for my truck to avoid costly drivetrain damage. Great product for Ford owners doing their own differential service!👍

Had a Auburn limited slip installed on F-150 a few years ago. Install shop used the Auburn recommended mix of 80-90 non-synthetic hypoid gear oil and Auburn limited slip additive. Axle began to shutter/chatter 300 miles later. Added a bottle of this Motorcraft stuff and problem completely solved.Fast forward to now: The shop that installed the Auburn posi didn’t seal the diff cover very well it would seep around the bolts and collect grime. Finally it began to drip. Decided to change rear axle fluid mostly so I could have a shot at finally sealing the diff cover correctly,This time I used Mobil1 75-140 LS gear oil. That’s full synthetic and is supposed to have limited slip additives included. Chattered bad. Then I added a bottle of KW limited slip additive. Chattered as bad or almost as bad. Then I added a bottle of this Motorcraft stuff. Instantly chatter free yet again!Yes it stinks something fierce. Even after cleaning my oil catch container with brake cleaner and letting it dry outside for an hour the remaining invisible residue stunk up the garage. Wear gloves and be careful so you can minimize drips and residue.But it also WORKS! For my situation it’s been that only thing which has.Side note: Recommend Permatex “Gear Oil Formulated” RTV to seal the diff cover. Good consistently, nice gray color, and is resistant to friction modifiers breaking it down. Rear axle is finally bone dry on the outside.

Great product for friction on posi traction rearends.

Messed with this stuff after my Ford van started shuddering around 185k miles. Saw a YouTube guy use it, so I did a big fluid swap and poured this in while the kids were inside asking when we’d be done. Drove a few hundred miles since. No more shake. Glad I tried it.

Great product at a good price

It does exactly what it’s intended and it’s genuine ford motor company and I used it on my F-150. Beware though it reeks. It smells like 10 year old burnt gear oil from a final drive condensed into a tiny bottle. Open a door before you open the bottle

A must for your clutches

Requirement for Ford differentials. Pricy on here but delivers quick.

This does exactly what it’s supposed to do and worked very well for my application. As far as performance goes, I have no complaints.The smell, however, is absolutely terrible and incredibly persistent. If you spill any, clean it up thoroughly and immediately, don’t just wipe it up. I spilled a small amount on my garage floor, wiped it up and figured that was good enough. It wasn’t. I should have mopped the area because the smell lingered for days.I’d also recommend getting the empty bottle out of your garage as soon as you’re finished with it.Good product that does its job well. Just treat a spill like a chemical emergency for the sake of your nose.