PowerTrax 1821-LR Lock Right Locker for Ford 8.8" 31 Spline, 3/4" Shaft, Compatible with 1983-2014 Ford Models

Works perfectly in my gm 9.5in 14 bolt semi float axle for my 93 blazer. Read the instructions i installed it the hard way with the springs and pins installed when putting it into the carrier instead of slipping them in thru the side as it was designed. I got it for 367$ which beats summits price by about 300$ engages smoothly under load when I want it to but it is rough on the locking and unlocking when idling in gear thru parking lots but I think its only because its a manual. Seems pretty stout and fit with the original thrust washer shims that it came with and the cross pin fit better then the original. We'll worth the money. I might even consider one for my c1500 with the same axle for a street truck as the street manners is better than expected unless you're hot rodding it thru the turns then it'll chirp the inner tire or break both tires lose

Pros -it works great off road and in the snow, totally locks the diff up, easy to install. IMPORTANT axle end play specs, set them right!! Wife drives the vehicle and doesn’t notices it. on road works well also. Cons - install manual sucks, clunky at times, hard on tires. It is easy to install. Unfortunately in the Chrysler 9 1/4 diff I installed this on came with Posi case. And the original part I ordered was the one for the Posi case. I didn’t fit, called tech support to verify I had the right part, they were quick to help. Unfortunately I had to order this locker along with new open case $135 new spider gear set $70 “just for the shims” the backlash adjustment tool $25 bearing set $100, fee to get the bearing pressed on $40, and backlash gauge for $30. I installed this on a 1999 Durango 4wd. The installed required a lot more work also had to weld the abs/speed tone ring to the case because when installing the original ring gear to the new open case. The tone ring had enough clearance to spin free. Time consuming and annoy. But the locker works fantastic. On road it’s mildly noticeable clicking around turns and clunky at times. But overall not a big deal, my wife drives the Durango often and has never complained about it. Video upload was with vehicle in 2wd.

Directions could be clearer, but after some thinking and video watching, once installed, the locker works perfectly! And for anyone looking for a locker to do some burnouts with, this will work!

I have a 1998 Toyota T100, 4x4 with the 8.4 axle. I was looking for a new solution to replace my stock open differential once it finally gave up after 26 years of solid use. Came across this PowerTrax 1615-LR Lock-Right Differential Lock Assembly. $300+ was a good price. Locks up in off road use and should lock/unlock on the street. Easy installation. Had a shop look over my work and they said it looked good. Seemed to work pretty good the first 2 months. Did the break in period, swapped out the diff oil. Did everything you're supposed to do. Then I started to get some slamming coming out of the rear differential. Felt like someone was crashing into the back of my truck. Asked many of knowledgable people about how these worked and if that kind of clacking and punching was common and they all said, "Yea. Those things are notorious for all kinds of weird sounds and actions." So I continued to use it. Well, as of 10/25/24 (8 months since I bought it), I'm replacing it with an electronic locker. As you can see from the picture, all the teeth are rounded off and the pins and springs seats are broken. Showed the gear and axle shop my differential and they said that this is common for these kinds of lockers.

Lock Right is a great invention. Simple yet very effective off road. It eliminates the weak point of a differential off road; transmitting the torque to the wheel with the least traction and causing you to stall. There are 2 forces that influence the Locker. One is delivered from the engine through the drive shaft, the other comes from the wheels due to different rotation speeds. The first force causes the Locker to lock while the latter causes it to unlock. Off road, where there is little traction, the force coming from the engine “prevails”, locks the Locker and ensures that torque is delivered to the wheel that is on the ground keeping you moving forward. On tarmac the situation is different especially during turning. Here you need to be very careful with the accelerator. The wheels’ uneven rotation tell the Locker to unlock. However, if you press the accelerator, the drive shaft tells the Locker to lock and now you have a fight. This fight is translated into loud knocking sounds that are unpleasant at best but can also cause vigorous rocking of the car (especially in manual gear transmission). By the way, normal behavior while turning is a clicking sound, which means the Locker unlocks. This is one sound that you need to get used to. I did not drive yet on wet tarmac, but I imagine you need to be extra careful during turning since there is not enough road traction to unlock the Locker and you might have to deal with a spinning car. Bottom line. If you can live with the disadvantages of the Locker in day to day driving in order to have better off road experience, install it.

Nice locker, however, it did not fit my Jeep as advertised. My jeep is a 1962 and at some point, they changed to a 19-spline axle instead of a 10 Spline axle. No one's fault just changes in parts by the MFG that was not listed on some early models. I would recommend it to anyone that needs a locker. Very heavy and robust. It also works on the split axle with the space in between the axles.

Installed in a 8.5 10 bolt open carrier. Went into a c10 with 5.3 4L60 and 275/60/15s. Install was breeze, just go read Motortrends install write up and it’s smooth. I was able to push the springs in the just my fingers and it went fine. I did install with the ring gear on but out of the truck, but doing it while still in the carrier wouldn’t be an issue either. TIPS FOR C CLIP AXLES—Just be patient, work the axles back and forth while holding clips in and you will eventually get the spacers in to cover the clips. I used a knife in the center, it’s a pain in the a..but keep working with it. I used 2.25ish quarts of 80w90 Lucas, I do have turndowns but I heard the clicking a couple times but nothing bad. If you’re around 10ish percent throttle, you may can take a sharp corner while clicking but it could lock halfway through. Again, not bad, I dig it actually. Second, when you let off the throttle, then get back on it, it may feel a little odd..a shimmy maybe but you don’t even have to touch the wheel. It’s not bad at all. If you’re getting this for the street, I strongly recommend just be sure to understand the trade offs ( chirping sometimes, a clunk or two some, clicking) If it’s chirping in a corner, it’s very easy to just throttle up a bit and it’ll spin on up easier than you think. Just don’t fear a locker, get it! I will update if any issues arise.

It was an easy install based upon the video I found on YouTube. The instructions were just useful enough to get a bon fire lit. Full of misspelled words, images so grainy it looked like it was taken on an iPhone 3g. Pretty sure they give an intern an old flip phone and a windows xp computer with Word on it and he wrote this manual. The product is quality. The company is nonexistent on help though. I'm not going to get involved with that on here, but they don't answer emails or do anything. But the product is quality built so that's why it gets 5 stars.