FordGenuine XL-3 Friction Modifier Additive - 4 oz.

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!!

I was advised by a transmission shop to use this product in my Jeep Liberty which was experiencing intermittent shifting issues.Truly amazing in that after one dose of this stuff the issue (shaking and shifting issues) have gone away and after several months and several miles the issues have gone away.

Used Royal Purple 75w140 and additive. Rear-end chatter is gone after 75 miles. Will purchase again. Don't mind the odor, you won't smell it again after the job is done.

The product is fine. Works as advertised but the smell is like hypoid gear oil on steroids!My rear diff has a dipstick which also serves as the fill port. Did the job outside, but threw the bottle away in the garage, along with a rag. Wow, the garage and first floor of the house reek, even with all remnants of the job bagged up in the back of the truck outside.Use caution!!

I’ve tried other additives and oil with friction modifiers, but this is really the only thing that I’ve found that make trac-loc differentials with the way they should quietly. Doesn’t smell the best though.

Very strong smell. Make sure you are out side or a good ventilate area. Good price

I used this in my ‘03 Tundra limit slip differential as recommended on one of the Toyota forums. I used it when replacing the rear end gear oil. Seemed to work fine. It seemed to do what it is supposed to do for the limited slip to keep it working.

Very happy with product.