BMR Suspension's BK051 POLY Diff Lockout Kit: Close-Up Look, Pics and Info!

Coming soon is our new Poly Diff Lockout Kit, Part # BK051.

Some of you who are close to us, and communicate with us on a regular basis know the time and effort we have put into this specific product - for those who do not know, we have been working on this product for well over a year now. It has not taken us a year+ to design it - but it has taken us this long to thoroughly test, revise, test and break parts over and over!

One of the first things I found to be an issue with the OEM's Diff mounting method was, the fact that the M14 bolts being in shear (and the shear forces being placed on the threads) was simply not up to the task for a quick "re-enforce and go" for the racers and the high powered enthusiasts, especially the stick shift applications.

I wanted to make this thread to show some pictures of some of the pieces in the kit.

-First off, is our hardware. We pride ourselves in using the best hardware we can get our hands on. With all of our products, we offer at a minimum, a zinc coated Grade 10.9 that is equivalent in size, OR larger than OE spec.

The hardware with this kit, will feature (6) bolts and supporting pieces to install the BK051 Diff Lockout Kit...with no issues. *ADDITIONALLY, hardware is included, for those who race their cars, or are making high power levels and want a piece of mind. So we include (2) GRADE 12.9 Allen Head Bolts, that install from the center of the cradle, back towards the rear of the car. This ensure MUCH MORE shear capacity, by removing the shear force on the threads and placing it on the shank. By putting those loads on the M14 Grade 12.9 shank...instead of the threads, the strength increase is staggering. Pictures of these bolts installed on our test mule will be at the bottom of the photos.

-Poly Diff Lockout Pucks, we designed and tested these bushings 100% in house, and have them made by a large Bushing Manufacture that is located within the US.

These Pucks are made of high quality 95 Durometer Polyurethane, for maximized performance and a longer lasting life. We designed these pucks to fit snug and tight within the front and rear bushing voids, and made them all (4) the same to help keep costs down...and make installation easier for the end user, as you cannot mess it up.

-NVH levels. We have found that no matter what you do - if you want true performance from the IRS / Diff....you cannot avoid an increase in NVH. This BK051 Kit from BMR is definitely our lowest NVH level Differential Modification though. Personally, I think the NVH increase is extremely minimal and it does not bother me one bit.

-Provided Bolt Upgrade, it works! Test, test and more testing! That is out style. We have seen so many differential bolt failures up to this point, that we simply could not release this kit to the masses with atleast giving them the best option for strength. To prove how common this is, I recently had a customer who was on the dyno with his turbo S550 here locally, contact me for help after he actually had a differential bolt BREAK on the dyno! Not even on the street. This bolt failure cost him a lot of money, and he ended up going with a BMR Diff Solution that I assured him would not fail. At the time he was not a BMR customer, but he has since acquired a few BMR items since this incident. Fairly common for people to come to me at some point when they make their cars faster and more powerful. :cheers:

The bolts we provide, I have had on test cars across the country for almost a year now...and we have tested them on our cars in house, thoroughly. I have yet to see one bend or break, and I have full confidence in them.

PRICE POINT: This kit, BK051, will be $59.95

NOTES:

-The bottom two pictures are only to show our bolt upgrade - those are not the BK051 Installed, those are the BK049 Poly Bushings...which are what we first noticed bolt issues with.

-The bolt upgrade is not plug and play. You have to ream the diff ear threads out slightly, and you have to make very minor grinds to the mounting pad for the bolt head (which can be seen on the last 2 photos)

Kelly, would these work for the differential on auto transmission cars?

They sure will. I have used them on my auto car.

BMR Tech said:

They sure will. I have used them on my auto car.

Click to expand...

Thanks man very cool! Looks like a lot of R&D went into this and preventing problems. Hard to believe that's only $60. If that was sold by Ford they'd charge 3-4 times as much or more.

What the advantages of differential bushings? Quicker acceleration off the line perhaps, better connection of engine and driveline? Perhaps better handing slightly maybe even on throttle situation in corners?

I'm having trouble getting a good 0-60 time. I need better tires first but I'm waiting til spring to do that so I can get summer tires. I'll have to put this on my list along with CB006 and LCA bearing kit.

You pretty much summed it up.

The issue with the differential moving around when applying power through the driveline, is that the working angles of the half shafts compromised, and the rotation of the differential housing promotes excessive oscillations through the parts that connect to it.

Removing the slop from the bushings on the differential allows for more effective power being applied to the wheels, helps combat drive-line vibrations by keeping the drive-line working angles in a better range, and just makes for a better overall performing and feeling vehicle.

As for the $60 price tag - this stuff cost very little. The bushings are low cost, and the hardware cost is very low due to the volume in which we acquire it.

We have a formula that we use to price our components. If you see a part we offer with an unbelievable price point, then it just means that we do not have much cost into the product.

Hmm, I wish this was available a couple months ago while I was contemplating my cradle bushing replacements. I had the exact same thought about those bolts. I ultimately ended up playing it off in my head, by thinking Ford would of used a sufficient bolt. I have the BMR delrin kit.

DAVECS1 said:

Hmm, I wish this was available a couple months ago while I was contemplating my cradle bushing replacements. I had the exact same thought about those bolts. I ultimately ended up playing it off in my head, by thinking Ford would of used a sufficient bolt. I have the BMR delrin kit.

Click to expand...

The BK048 Delrin Kit is a great kit for the cradle! I believe it to be the best solution, as the Delrin is a great material...and the fact that we ensured the bushing tops to chassis had more surface area than anything on the market - and still do. I also like the sleeveless design, to help combat NVH increases :cheers:

What did you end up doing for the diff mounts?

It sounds like from what I'm hearing from Kelly - this is a very worthwhile upgrade even considering possible small NVH increases. When you have a car with 435+ hp, seems to me it's very important that your differential is helping to put the power to the ground as effectively and seamlessly as possible. I have gotten over my NVH concerns now. I just learn to accept and embrace it!

Even just for safety reasons. Seems to me if the differential is applying HP/TQ more effectively, the interaction of tires to ground will be much more predictable, making us go faster potentially and more importantly safer.

I had avoided the differential part of this in my mods as it seemed the least necessary and possibly more time consuming. But now that I think about it- it seems maybe more necessary than I initially surmised.

Making the diff mount more rigid makes a significant difference.

Most people who contact me direct, will confirm that I have usually recommended addressing the diff solutions lastly...and most times, only end up firmly recommending the solid pieces (usually racers approach me most about diff parts)

The reason is because we learned early on about these bolts, especially the rears, having durability issues.

On that note, I hope these are available for order within the next 2-4 weeks. ;)

I like the idea of the stronger bolts in the diff, especially with how I track the car. Would I have to drop the entire diff to make the modifications necessary for these new bolts?

You can slightly lower the cradle and perform the modifications.

I just noticed another company announce a hardware upgrade kit.

While the 12.9 is greater by a large margin in tensile strength, the 12.9 change from 10.9 does not increase shear strength by much, compared to actually increasing the diameter at the shear points.

The ultimate way to do it, is by placing the bolts in a fashion that the shear load is on the actual SHANK...and not the threads.

BMR Tech said:

The BK048 Delrin Kit is a great kit for the cradle! I believe it to be the best solution, as the Delrin is a great material...and the fact that we ensured the bushing tops to chassis had more surface area than anything on the market - and still do. I also like the sleeveless design, to help combat NVH increases :cheers:

What did you end up doing for the diff mounts?

Click to expand...

Nothing, like I said I put it back like I found it, and prayed to the gods. Not the best solution but if you have wrastled a rear cradle, I think you know the feeling at the end of the day. LoL

haha yes.

I actually have a few people using these rear bolts with stock bushings.

Cant go wrong!