kenworth frame rail

Pretty common for all trucks frame to crack I know kenwort frames were common to crack on the earlier 8 bag suspension behind the lower arm frame mounts.it would be better to replace the rail but it can be fixed. I would take it to a shop that stretches frames if it were me I would repair the crack on the frame and the at minimum sleeve the frame it would not be wize to try and gals ##### it not worth your life or anyone else's in my eyes just my .02

 

Seems to be really common on the W900. the crack usually starts on the bottom flange of the frame where the shackle bracket is riveted on. What we do is get a set of shackle brackets for a k100 and use those instead of the w900 brackets. this gets rid of having the rivet in the bottom flange of the frame. We jack it all up so the frame comes back together and then vee out the crack and weld it up. We next get a length of frame rail and cut the bottom flange off and run it inside the old frame from the very front to right in front of the rear engine mounts. drill any holes you see in the original frame and bolt it all together. sometimes we add a couple holes if we don't think there is enough. then put it back together with the k100 shackle brackets and have never had one rebreak.
The w900's are known for cracking in this spot and often times goes unnoticed because the power steering resivoire hids the crack

 

how think is the rails on your W9.

I pulled in my Century for a 50,000 mile semi-annual today.

Just behind the cab mount on the drivers side, we found a crack just like you describe.

I have a 1/4" thick rail.

 

RHay, I have a T600 I want to do this to. It has the one hole in the side of the frame and one underneath in the flange. I'm assuming this is the same as the W9's are. Are all K100 brackets the same? Where do you get yours? Do I need the K100 shackles too, or reuse mine? I just bought all new pins and bushings for the front end, but decided to put it on hold till after I learn more about this mod. Hopefully the T6 bushings fit in the K100 brackets.

 

Used to work for a company that purchased W9s, T6s, & T8s; to my knowledge we had few, if any, problems with the W9s and T6s used as hwy trucks; the W9s and T8s that were used in the oil patch was a different story. Reason was due to tight locations- everyone screwed in the set stops, or tried to adjust the steering box for a tighter turn radius. IIRC the W9s developed cracks in the same area as yours, also passenger side near spring hanger. I think the T8s would more often crack on pass side, steer axle rear hanger.
In late 1980s, or maybe early 1990s, Kenworth had issued a bulletin concerning this- a copy was sent with each new truck purchased by my company informing purchaser that warranty would be void if tampering with the steer box or set stops was noted. After your repair, you may want to check that yours are in correct adjustment in order to hopefully prevent future problems.
Good Luck !

 

Hello, I know this is a fairly old post so I'm hoping someone will still reply. I have this same exact failure on my 99' W900L right now, I am looking for a part number for the K100 front shackle. It appears to be that there is more than one and my KW dealer doesn't seem to be aware of the problem or a part number for the K100 shackle, any help would be greatly appreciated. Thank you!

 

I have a 95 I'm preparing for this to happen to one day. A guy told me the last 6 of the vin for his 96 k100 which you should be able to have kenworth look up the spring hangers for that truck with his last 6.

380869

 

What thickness frames are you guys having this trouble with, have not had this trouble and my stops have been screwed in for years, off road severe duty too.