Theory on preventing frame cracks around steering box and panhard bracket (2 Viewers)

[PeterTheBeater]

Well, resurrecting this thread. When I’ve got my cruiser (totaled), the PO only showed front quarter panel damage. A year later noticed a crack in the panhard bar. Had the weld repaired with stick by qualified welder. Fast forward 7 years, installed some new control arms, was driving down 25mpg steering wheel started to wobble, like my wheels were falling off. Got out and double checked everything and it was good, when got home however, noticed that the panhard is now cracked at factory weld.

Ordered a delta vs kit and going to try and repair it.

 

[landtank]

4day drive out to San Francisco toeing a U-Haul trailer. Hit a nasty pit hole resulting in a crooked steering wheel.

Got a local guy to weld the cracks so the wheel’s straight again and with Dave’s help with a kit and a call to a fellow 80 guy the plates are going on Sunday.

I feel very fortunate to have such support from the community. MA is still a long ways away especially with a cracked frame.

Thank you

 

[808keith]

I found out why my 80 was suddenly started to wander again. No parts old or worn on the front. With my son moving the steering wheel back and forth, I could see the crack at the base of the pan hard bar mount. Time to bust out the welder and see how I can best reinforce this.

 

[PeterTheBeater]

I found out why my 80 was suddenly started to wander again. No parts old or worn on the front. With my son moving the steering wheel back and forth, I could see the crack at the base of the pan hard bar mount. Time to bust out the welder and see how I can best reinforce this.

View attachment 3947018

That sucks…make sure you put in reinforcement or it will happen again.

 

[808keith]

That sucks…make sure you put in reinforcement or it will happen again.

Yes. I have plenty of scrap steel. I’ll drink some beers while I ponder how I want to do this

 

[mudgudgeon]

Yes. I have plenty of scrap steel. I’ll drink some beers while I ponder how I want to do this

If you're looking for a solution with random scrap, here's what I did

Find the extreme ends of the crack,
Drill 2-2.5mm hole through the frame at each end of the crack,
Clean up and re-weld the crack,
Gusset between the outer corner of the frame rail and panhard bracket with 1/8" x 1" flat bar,
Stitch weld gusset in place.

My thoughts were, a gusset transfers the bending moment from the middle of a flat surface (underside of rail) to the corner of the frame rail. It's a more rigid part of the rail.
The welds for the gusset are away from the fatigued metal around the crack.

 

[808keith]

If you're looking for a solution with random scrap, here's what I did

Find the extreme ends of the crack,
Drill 2-2.5mm hole through the frame at each end of the crack,
Clean up and re-weld the crack,
Gusset between the outer corner of the frame rail and panhard bracket with 1/8" x 1" flat bar,
Stitch weld gusset in place.

My thoughts were, a gusset transfers the bending moment from the middle of a flat surface (underside of rail) to the corner of the frame rail. It's a more rigid part of the rail.
The welds for the gusset are away from the fatigued metal around the crack.


View attachment 3947056View attachment 3947057View attachment 3947058

Thanks for the idea

 

[Broski]

FWIW the DIY solution in post #7 get my vote as one the best fixs offered.

 

[808keith]

Stitch welded some angle iron to help spread load along and edge of the chassis and box tube ties it into the pan hard bracket.

 

[SNLC]

FYI Toyota fixed this problem when they added coil springs to the front of the 70-series in 1999.

They moved the steering box forward, pitman arm swings back, by doing so they separated the panhard and steering box mounts.

I have never heard of this being a problem or even heard of any 70-series with cracks at the panhard.

So ya, bit of a design flaw they fixed.

I have looked at doing the same on an 80-series. It’s doable although you are going to have to remove the front frame crossmember and replace it with the 70-series. The radiator is also a problem and in the way, it’s taller and narrower on a 70-series. In other words a major custom project I didn’t feel like messing with once I explored it.

Cheers

 

[PeterTheBeater]

Stripped as much as I can to weld the new brackets on. The outer fit is good, inner fit needs to be trimmed on few spots.

Definitely going to be a challenge to get to the top inner bracket, especially with those brake lines in the way.

 

[Broski]

View attachment 3948851
View attachment 3948852

Stripped as much as I can to weld the new brackets on. The outer fit is good, inner fit needs to be trimmed on few spots.

Definitely going to be a challenge to get to the top inner bracket, especially with those brake lines in the way.

IMO those plates mostly address steering box issues. There not going to do much for the side to side forces the Panhard mount see.
The out side one could be useful to tie a brace into like the one @Richardlillerd! used in post #7 or the one @808keith made in post #49
@mudgudgeon uses the same logic in his post #43 brace the mount to reduce side to side motion/flex !
Unless the frame is cracked around the steering box mount I would not use the inside plate as it's to hard to get a proper weld let alone Prep /clean the area for a good weld. if the motor was out that would be a different story.
I'm by no means a engineer but I would like to see the holes in the out side plate bigger to allow more penetration of the welds.

Now I'm going to inspect my mounts to make sure I'm ready for SAS

 

[Broski]

All good

 

[PeterTheBeater]

Yeah there’s an additional brace that’s not pictures, but I am going to brace that more than just the brackets.

 

[Outsane]

Got a visit from @landtank

Welded in the @Delta VS plates

@Broski here you can see the plate that supports the panhard bracket to the steering box mount.

Here is the top of the plate on the inside, had to stuff my head pretty far up there.

 

[PeterTheBeater]

Got a visit from @landtank

Welded in the @Delta VS plates

@Broski here you can see the plate that supports the panhard bracket to the steering box mount.

Here is the top of the plate on the inside, had to stuff my head pretty far up there.

Did you have to trim the inner bracket? The “ears” on seem to be off a bit. Looks like it’s the angle of the panhard bar bracket

 

[Broski]

Got a visit from @landtank

Welded in the @Delta VS plates



View attachment 3949021
@Broski here you can see the plate that supports the panhard bracket to the steering box mount.

Here is the top of the plate on the inside, had to stuff my head pretty far up there.
View attachment 3949022

Well done !

 

[Outsane]

Did you have to trim the inner bracket? The “ears” on seem to be off a bit. Looks like it’s the angle of the panhard bar bracket

I did trim a little, I think the angle changed from the fj80 to the fzj80 chassis

 

[reklund5]

Added the Delta reinforcement plates when I did the engine swap last fall. I feel like it was definitely worthwhile.

 

[DivByZero]

I have a set of plates from Rampt Customs here in Australia on the parts shelf:

Rampt Customs 80/105 Landcruiser - Steering box brace kit

A known weak point in the 80/105 Series Landcruisers, is the chassis where the steering box mounts, as well as the top section of the panhard mount. We have seen many completely stock Cruisers with cracks in this area. Unfortunately once you start adding lifts, bigger tyres & some offroad abuse...

www.4x4andcamping.com.au

It's been waiting on timing, but I'm expecting to be swapping out the engine on my 80 in the next 6-8 months. Plan will be to tow the rig to an experienced shop and get them to weld these in for me when the engine is out.