Has anyone experience this crack before?

[nissanh]

I saw this crack on rear left shock mounting plate.

The weld is intact however, the metal right below the weld is tearing apart. Must have been taking place for a long time.

Last Picture is from T4R member Scramble

Weld it? Any suggestions?
Thanks

 

[brillo_76]

I seen that area rotted out on a few of mine. Cracked so it has to be an extreme stress fracture that's going to need welded. You jump the 4 runner or do heavy off roading?

They are only welded on 3 sides with that crossmember tube weld being the weakest.



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[nissanh]

I seen that area rotted out on a few of mine. Cracked so it has to be an extreme stress fracture that's going to need welded. You jump the 4 runner or do heavy off roading?

They are only welded on 3 sides with that crossmember tube weld being the weakest.



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Not at all!

The weld at the tubular cross member is also has come loose. Dropping the gas tank is not too bad but love to avoid if I can.

How about weld the torn and run two high tensile nuts and bolts from the tubular cross member to shock-mount plate as shown below to avoid the requirement to drop the tank to weld that area?

 

[Dieselchessy]

Maybe you added longer shocks but didn’t extend your bump stops?

If you do that then your shock bottoming out becomes the new bump stop.

 

[nissanh]

good point

Maybe you added longer shocks but didn’t extend your bump stops?

If you do that then your shock bottoming out becomes the new bump stop.

A very good point, but I installed these shocks about 2 years ago and never been off road for past 3 years. The 4R is used by my wife for past 3-4 years. It has air bags installed and I keep it at 7 psi. No issues to the passenger side.

Temporarily I put a ratchet strap to pull the plate towards the frame.

Could the Bilstein is too stiff? Those who installed this knows how pressurized these shock are.

 

[brillo_76]

Ok. I just never seen that area crack nor that plate come loose on a non rusted one.


That plate wraps around the tube crossmember and welds on to it. I had one tube rot and the plate come loose as that cracked section was rotted away. Its only about 2 inch weld or less on that tube holding that plate to it.

Since it loose this makes more sense

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[brillo_76]

I dont suspect too stiff as those plates have the cushion stops in the springs. Honestly I have no clue how this occueed on a non rusted. Not heavily off roaded 4 runner.

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[Dieselchessy]

You don’t have to off-road to hit the bump stops on one of these 3rd gens with factory rear coils.
You put a good Costco run of groceries in the back and they will pretty well ride on the bump stops.

The drivers side has all the weight. It would be expected to fail first if something was going to fail.

What model rear shocks do you have?

 

[nissanh]

The shocks are Bilstein 33187174. These were installed on January 2019 by me (miles driven 2800).

There is about 2 inches of (polished shaft) travel length to bottom out the shock. I do have air bags installed so 2 inches of down travel (body) is not possible to bottom out the shock.

Anyways, I am thinking of installing OEM Toyota rear shocks now. I don't want this to happen on the right side.

Just installed a 14 mm Bolt from the top of the plate where the crack originally started to the out side of the frame.

 

[fourfive]

The shocks are Bilstein 33187174. These were installed on January 2019 by me (miles driven 2800).

What rear coils do you have paired with those bilsteins? The ones you listed, when used on 3rd gens, are for 3-4" rear lifts (890s, superflex, fzj80, 860s).

 

[phattyduck]

Are you sure that isn't 100% normal? That plate may be top welded only from the factory.

-Charlie

 

[turbo8]

Those shocks are for the next gen 4runner which are 2" longer compressed than the 3rd gen bilstein shocks. You would need to extend your bump stops to make these shocks work.

 

[brillo_76]

Are you sure that isn't 100% normal? That plate may be top welded only from the factory.



-Charlie

That coil shock plate is welded on 3 sides. If the weld breaks or comes loose on the crossmember tube. It will work and destroy the frame Weld on the frame rail. Well this is what happens when they are rusty. As that inner frame rail is only about half as think as the c section of the rest of it. I seen this on Tetanus 1 [1998 SR5]

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[nissanh]

I use tall springs form a 99 and a spacer 1.5 above the coil. Guess the spring got sagged really bad. I have a good set of tall springs from another 99 (marks are green and red).Thinking of installing those with OEM shocks and without the spacer and air bags.

Can anyone confirm the Toyota 48531-80693 are Tokico's?

I might list the Bilsteins for sale soon.

 

[Kanoe]

Can anyone confirm the Toyota 48531-80693 are Tokico's?

Yes. They are. Have a brand new pair waiting under my desk.

Be warned, they don’t come with all the accessories like aftermarket do. Look at the parts diagram carefully. That little baggy is all that come with the shock.

 

[brillo_76]

So what's the consensus as to why this shock coil plate cracked and was tearing off the frame?

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[nissanh]

Most likely cause is bottoming out the rear shock absorber and acting as a bump stop (thanks "Dieselchessy").

Now to the solution:
I have 1.5 inch spacers installed at front struts

1) Would the rear sag if I install tall 99 coils and OEM Tokico shocks (yet to purchase)?

2) Would you all recommend 1.5 inch rear spacer (above the coil) and stock tokico shocks or the Bilstein 5100?