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-   -   57" OKBJ Axles breaking with powerful engine (https://www.team-bhp.com/forum/4x4-technical/162202-57-okbj-axles-breaking-powerful-engine.html)

Nowadays, more and more vehicles are getting seriously modified for offroad, of which, day-by-day the bar is rising to an international level. Unlike abroad, we don't have even a handful of vehicles to choose from. Most of the options are seriously underpowered. So, no wonder most of them go through an engine swap.

The most common problem with these engine swaps (jeeps) are the front axles breaking, especially the 19 spline, 57" Open Knuckle type ones. However, there are fewer problems with closed knuckle ones, and there is absolutely no problem with the axle tube. Even if you jump 5 feet in air and land, nothing happens to the front axle tube. I've seen the leaf spring and shock mounts on the chassis crack, but nothing happens to the axle tube, and much fewer problems with closed knuckle type ones. The OKBJ type ones, most of the time, the axle breaks in longer side joint.

• Is it really the powerful engine that's causing the axles to break? I have a feeling its the engine/front end weight a main cause of breakage?
• Why are there fewer problems with the closed knuckle ones?
• Also, why is the open knuckle type ones breaking, which are supposed to be newer than the CKKP type.
• What weight/torque can a 19" OKBJ safely handle?

With the frequent axle breaking issue, Viji from Bangalore and Gautam from Coimbatore have CV joint solutions. Any reports on those? What load/weight can they safely handle?

Which part is breaking? generally the weakest link gives away.

In gypsies with large wheels and crawler ratios, if you get the front wheels stuck and try unnecessary powering, front joints would snap. Rear first sign would be the TC mount then axles, if both survive tube will twist.

From what i understand the new joints that are being imported should work and offer lifetime guarantee. But then keep a look out for the next weakest link. It is a never ending cycle :)

One needs to understand the limits of ones vehicle, that is the only way you can have a trouble free vehicle. One of the reason why i just can't relate to the wham bam events that are popping up around the country. It is definitely not offloading for me, no brains just brute force and momentum. Won't do it to my own vehicle lol

Yup. The front axle joint breaks.
Apart from the front axle joint, I guess rest of the drivetrain is pretty rugged. Yes, the next link with give way, but, just have a feeling its not as weak as these joints. Just wondering why the CKKP ones were more rugged than the newer ones.. :confused:
In a way, yes. Once you put in 'competition' its all wham bham types. Some guys try points, but just dont work most times.

Closed knuckle? If so, maybe the design of the knuckle and the metallurgy used. The premium for the imported axles is also due to the same reason.

And were these axles running the same engine gb combo that it can be compared?

Yup, AFAIK, Normal 550 51" CKKP front axles are stronger than 57" OKBJ. Everything else same. (Scoprio CRDe engine + KMT90 GB)

The CKKP is more relialble as the design restricts the angular movement of the front axle and hence its joints.

Cheers
Vijay

Hi Dhanush,

How many of the Vehicles with busted the front axle are running Negative Off-Set Wheels?

The OKBJ Axles are much stronger than CKKP type axles, the problem is everyone ignores the Axle UJ(star), the UJ needs servicing/replacement annually/bi-annually.

Regards,

Arka

All of them running the deep dish wheels..

But the point of failure in all cases is indeed the UJ star..

Hi Arka,

Almost all of the vehicles running negative offset wheels (-30) and 31 inch + tyres.
The axle star gives away, gets replaced with new, and it fails at the very next offroading trail. Some vehicles that I know have changed it atleast 3 times in one year.

Thankfully, I have broken it only once, and that's when towing a vehicle in reverse. I'm just waiting for my next turn, hence this thread.

Hi Prabhu and Dhanush,

Point of Failure has to be the Axle Star, otherwise you will lose a Hub or worse the Differential.

Now Negative Offset Wheels increase the distance of the contact patch to the Axle UJ, thereby exerting more leverage.

Also if the UJ Failure has not damaged the Axle Yoke, then consider improper installation.

Regards,

Arka

Thank you. Any idea on how much torque these axles can handle?

I broke two set of axles. one set with 30" tyre + lockers, one set with 33" + lockers. Now installed CV joint from Gowtham. Details are there in my thread http://www.team-bhp.com/forum/4x4-ve...ml#post3675527

Hi Dhanush,

1) The Low Pinion Dana 44 with 30 Spline Axles; MAXIMUM, Momentary torque Output is 4170 ft/lbs or 595 kg-m

http://en.wikipedia.org/wiki/Dana_44

2) Stock Axle Shafts 3,500 lbs. @ 35°

http://www.drivetrainshop.com/Dana_44_s/87.htm

3) Max Output torque - 4460 ft-lbs
Max Continuous Torque - 1100 ft-lbs

The 19 Spline Axle will obviously be much lesser than 3500lbs

http://www.fourwheeler.com/how-to/tr...-axle-anatomy/

Regards,

Arka