Lubegard 30903 Gear Fluid Supplement, 8 oz.

Replaced the old and neglected gear oil in my '97 Nissan D21 pickup with brand new Redline MT90. Thought it would improve the clunky shifting but it did the opposite. 2nd, 3rd, and 4th started grinding. My theory is that the old fluid had lots of wear particles in it that helped the synchronizers grab. The new synthetic fluid was too slippery and caused my gears to grind unless double clutching and shifting very slowly and deliberately. I added one bottle of Lubegard supplement and I could immediately feel the shifts improve. I still shift slow and carefully, but it's much more forgiving and the synchros grab much better. It feels like a different gear box now. Highly recommended, I will for sure buy more.

Another update May 2023: I've since used this in so many different vehicles not just by own but families and friends. It has helped on a couple of occasions quiet down a noisy diff, not completely but definitely quieter. And no chattering or noises from any of the Ford differentials I've put it in. Over several years of testing I can honestly say great product! Not sure if I would use it in a highly sensitive manual transmission though as it does reduce friction quite a bit which is a great thing but sometimes not so much in a manual transmission :) Update October 2018: The benefits i had noticed continued in the F250 while i had it (no longer have it) and also used it in a new application: a 2016 Ram 1500. I chose to use Redline 75w140 and this product as directed. The axle performed as i expected; very quiet. There is also LG in the motor and this truck runs beautifully. Average mpg over 24,000 miles is 19.9 combined. Not bad for a Hemi! I've used this product in my Ford F-250 in two different applications; the 4spd manual transmission and the rear axle. Using this product mixed with 80w90 in the manual trans made a considerable difference in shift quality, especially when cold. I also added a bottle in the Dana 70 rear axle w/ limited slip. Used Valvoline 75w140(contains friction modifier) and one bottle of Gear supplment. No problems after 500 miles and the axle is whisper quiet, no chattering. Lubegard isn't the sole reason the axle is quiet, but in my opinion a contributor. The LXE technology Lubegard uses has an amazing effect on reducing friction. I've used Lubegard's products in the engine, auto and manual trans, axles, coolant, and power steering with success in every application. Use this product with confidence.

Lubegard are the ONLY oil additives I have found - in decades of use - to be worth the money. I originally tried the ATF supplement for a serious transmission issue and it saved it. The chemistry of the ester oil is solid and works. I use the Biotech in engine oil, ATF in AT and PS applications, and the yellow in gear boxes of all types. It’s worth it.

Drain and filled my manual transmission with synchomesh and one bottle of lubegard. One day made a trip from Winchester va to Charleston wv , half way thru my trip kept noticing a burning oil smell. Got to Charleston and come to find out a seal blew and my transmission had ZERO FLUID left. No whining noises, warm to the touch. I’m a firm believer lubegard still kept everything lubed even with no gear oil.

Truck is old and has a lot of miles but it’s been decently taken care of. I do a lot of interstate driving for work and it developed a whining sound at highway speeds in fifth gear. Also some light grinding while going into third gear. I changed the transmission fluid and added a bottle of this to see if it would help. Since that I’ve drove the vehicle around 3000 miles with absolutely no change in any of the issues the truck had. I’m not saying this product doesn’t add some protection all I’m saying is it did not help with any of these issues.

Added to Subaru Outback front and rear differential and noticed a change immediately! Mileage even improved a bit, which wasn’t expected, as I was looking to extend the life of the current fluid- not necessarily solving a problem. It’s a trusted brand for me, so I’m not shocked it’s a good product that simply works versus “snake oil.”

This product improves petroleum based gear oils giving them performance similar to synthetic variants. I love Lubegards products and have used many throughout the years. My only advice is to buy this at NAPA because it’s $9.99 there not $19 + which is a total rip off!

always a good product