FJ40 Rear cross member and bracket replacement (1 Viewer)

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kiwidog

Kiwidog
Joined
Sep 5, 2005
Threads
35
Messages
347
Location
Red Deer Alberta
The start of the frame repair.

Removed most of the rivets by grinding the head of with 4.5' disc grinder.
Had to cut heads of some with the torch. Pried the brackets off then ground the remaining rivets flush with the frame and then knocked the out with 3/16' punch and small BP hammer

Had the local steel shop break a few parts.
Used 3/16 plate for all parts.

Removed the spring hangers and flatten out the flange on the triangle bracket. Easier to use as pattern.
Had the SS water cut and bend the flange on the on the bracket.
Used the old bracket to mark the holes for drilling.
Found some 3/8x1 round head rivet at a blacksmith supply store. 50 rivets (2lbs) for $10.50 plus freight.
Had the SS break the 61" long rear cross member (actual length 59.75")
Cut the tail light mounting holes with jig saw. Drilled 3/4 dia. holes in the corners and cut into the corners. Marked the holes with a carbide scribe. It is amazing how close to the line you can come. Very little clean up. I used 3.5x glasses to see better ( old eyes)
Measured the other holes from the original member and transferred them to the new parts for drilling. Used pilot drill 1/4" them 3/8"

Should be able to start assemble soon.
It amazing how accurate the holes and layout dimensions are on the original parts. I think Toyota engineers must have worked with tolerances of maybe 0.2mm or 0.008". on the frame parts, amazing, and this largely without computer controlled machines.

The cost of the rear member was $70.00
The two water cut brackets $75.00
This included the material and the shop time to break and water cut.

Thanks jb
frame 1.jpg
frame holes.jpg
frame triangle.jpg
 
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Frame pictures

Few more pictures.
frame 2.jpg
frame 3.jpg
frame 4.jpg
 
Splangy

Hi,

Any larger fabrication shop will have some sort of shear and break.

If you take them a drawing with dimensions on it, they should be able to do it.
The picture should include the material thickness and length and quantity ( 1of )
It's the inside dimension of the U shape and the flange length outside that are important. You specify that and operator of the break will work out the width of the flat piece he has to start with. There is a formulae for the bend allowance. They would be very aware of what is required.
Depending who you get as your first contact at the shop, these blue collar guys are usually very interested in small projects and restorations. Don't be intimidated by them, just try to use their language, break instead of bend shear instead of cut, although they do use "water cut".

If a guy was going to do a bunch it would best to flatten out the old and use it as pattern and have all the profiles on the ends and the light sockets cut on the water jet before the u was formed.

I could certainly get a rear cross member fabricated for you. The freight would be killer?
Unless you live in area where there is no fab. work done, it would be way cheap to get it locally.

The U shape dimensions are 3-15/16" inside and the outside flange length is 2-1/4" and 3/16" material. (mild steel) If you want to be cute specify a tolerance of +/- 1/64" The may grunt at that, and have a bit of fun with you.
Let me know how you make out, if you really need a piece made let me
know.

As for "bucking" the rivets,(not too far "f"rom the other term) a ball penn hammer and maybe some heat. May try the small air chisel if I can make a head that has the approximate shape of the formed head of the rivet. Suggestions are welcome.

Thanks jb
 
Ive done the same work on my 81, but the rivets I skipped! I bought them and tried several methods. Since I work on aircraft I had the air rivet gun and many bucking bars. I even tried to buck them after I heated them cherry red hot. I just didnt have the equipment that they used at the factory! I used grade 8 bolts and welded around most of the seams. Good luck I hope you find a way, and your parts look great!!
 
Texas81FJ40

Installed the spring hanger bracket on the frame gussets.
The two rivets are round heads in between the side supports of the spring hanger and countersunk and flush on the top side.
It's a lot of beating to get the rivet tight in the gusset.
I may take your suggestion and use 3/8 grade 8 bolts.
The angle bracket which go from the frame rail to the rear cross member are held on by 4 rivets each. Would like to have them riveted so that it looks somewhat original. Think you can install them on the cross member first so the work is on the bench and near a vice.
Know one thing it is better to drill the holes in the cross member first and then use them as a guide to drill the triangle gussets, that way you can work from the outside.

Didn't get a whole lot done today had to do a little woodwork. The banister at the top of the stairs needs a short piece of hand rail as a return back to the wall.
Used an old style pattern for the other handle rails in the house, so it was a matter of fabricating something to match. Only needed 38 inches however it takes just about as long to make as an 8 foot piece.

Will post some more frame progress soon.

Thanks jb
frame gusset.jpg
cross member.jpg
handrail.jpg
 
Your work looks great! I totally understand the "original look" you are wanting to go with. I pondered that thought for almost two weeks. I wish you the best of luck!!!
 
I'm contemplating how to build a new Rear Crossmember, but considering a piece of 2x4 rectangular steel tubing and cutting away backside.

Is that too much work or too ghetto?

I would buy a pre-made one from some of the typical 40 sites but too expensive, especially after shipping.

Would it cost less to have one bent up?
 
Very nice work! I am in the exact same boat on my 81 BJ, Except I think mine is a little further gone than yours...

:doh:
P5260105.jpg
 
Hi,

Any larger fabrication shop will have some sort of shear and break.

If you take them a drawing with dimensions on it, they should be able to do it.
The picture should include the material thickness and length and quantity ( 1of )
It's the inside dimension of the U shape and the flange length outside that are important. You specify that and operator of the break will work out the width of the flat piece he has to start with. There is a formulae for the bend allowance. They would be very aware of what is required.
Depending who you get as your first contact at the shop, these blue collar guys are usually very interested in small projects and restorations. Don't be intimidated by them, just try to use their language, break instead of bend shear instead of cut, although they do use "water cut".

If a guy was going to do a bunch it would best to flatten out the old and use it as pattern and have all the profiles on the ends and the light sockets cut on the water jet before the u was formed.

I could certainly get a rear cross member fabricated for you. The freight would be killer?
Unless you live in area where there is no fab. work done, it would be way cheap to get it locally.

The U shape dimensions are 3-15/16" inside and the outside flange length is 2-1/4" and 3/16" material. (mild steel) If you want to be cute specify a tolerance of +/- 1/64" The may grunt at that, and have a bit of fun with you.
Let me know how you make out, if you really need a piece made let me
know.

As for "bucking" the rivets,(not too far "f"rom the other term) a ball penn hammer and maybe some heat. May try the small air chisel if I can make a head that has the approximate shape of the formed head of the rivet. Suggestions are welcome.

Thanks jb

This sounds like exactly what I need.. 'cept I don't understand anything you are saying! I did find a large metal fab shop near me that I was going to go see, to ask about making a custom expanded metal storage box and mounting bars for a rear bench seat (over the wheel wells). Maybe I could get them to make me a new rear frame crossmember? Another stupid question.. how do I paint this? I'm not sure the diff between "powdercoat" or enamel, or whatever. Just something nice, shiny, durable, and black. Original looking.

Here's my current rear, with a custom bumper and jeep lights. I'd like to go to a more orig FJ40 look, with the rectangular tail lights.

607619863_eQQ7V-M.jpg

607619786_2sDQM-M.jpg


It looks like the orig frame crossmember is still there, but the ends were chopped off, and this custom diamond plate bumper was just bolted on. Could I just unbolt this, and somehow restore this to accomodate the late '70's rectangular FJ40 lights?

Or.. I can go to SOR, which is sort of local to me. But, this item seems discontinued or out-of-stock, and is expensive. In stock, but also kind of pricey at Man-A-Fre. Maybe I'll drive there and see what they can do for me. At least I wouldn't have to pay outrageous shipping.

Ok.. thanks for the advice!!
http://yew.smugmug.com/Cars/FJ40/IMG6154/607619786_2sDQM-M.jpg
 
nobody cut any ends off you still have your stock rear crossmember - if i remember correctly we showed you the wrong one in that other thread where you first showed pictures of your truck.. give me a sec while i dig up a picture of a rear which is accurate for your year.. it might be easier to convert back to a stock look than you think

pictures are courtesy of MY64FJ40


you might find this interesting.. https://forum.ih8mud.com/40-55-series-tech/119768-early-tail-light-bracket-help.html
My64FJ40.jpg
MYFJ64.jpg
 
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It looks like the orig frame crossmember is still there, but the ends were chopped off, and this custom diamond plate bumper was just bolted on. Could I just unbolt this, and somehow restore this to accomodate the late '70's rectangular FJ40 lights?


The cruiser in the picture is a pre 73 and would of have round tail lights. On those the rear crossmember was shorter and doesn't look to be cut.:cheers:
 
just a heads up if you plan on converting to the later model crossmember - you might run into trouble with the crossmember interfering with the body at the edges as well as slight differences in body mount locations - just a heads up that someone can maybe confirm
 
I just recently got a quote from a local machine shop to bend a rear crossmember up using Kiwidog's specs 3/16" metal = $260.

So I went back on the hunt and found an eBay vendor out of Michigan who sold me a Super Heavy Duty Rear Crossmember for $159, rear spring gussetts for $89, rear 2" hitch/receiver $85 and shipping to my door $31 !!!

I just finished removing the oem crossmember last night. Will post some pictures up later.



BTW, anybody know where I can purchase new rear spring hangers?
 
I just recently got a quote from a local machine shop to bend a rear crossmember up using Kiwidog's specs 3/16" metal = $260.

So I went back on the hunt and found an eBay vendor out of Michigan who sold me a Super Heavy Duty Rear Crossmember for $159, rear spring gussetts for $89, rear 2" hitch/receiver $85 and shipping to my door $31 !!!

I just finished removing the oem crossmember last night. Will post some pictures up later.



BTW, anybody know where I can purchase new rear spring hangers?

Are your old ones that bad? If not, just cut them off your old gussetts and weld them on your new ones. Oh, and you'll have to do some welding and drilling to get his rear crossmember to work on your '81 unless he finally got around to making '79-'84 crossmembers.
 
Splangy,

I was just trying to save myself some time behind my grinder cutting the hangers off the 1/4 plate metal.

I can see I might need to work on the rear body mounts. Bolt holes seem a little off, but not by much...

I've come to the conclusion that nobody's s*** is perfect !
:bang:
 
Splangy,

I was just trying to save myself some time behind my grinder cutting the hangers off the 1/4 plate metal.

I can see I might need to work on the rear body mounts. Bolt holes seem a little off, but not by much...

I've come to the conclusion that nobody's s*** is perfect !
:bang:

You're going to have to weld on a couple of 3/4" strips of 3/16" steel on the top inside edge of the crossmember and then drill new holes for the rear body mounts. His stuff is great quality and probably works perfectly for the intended years ('74-'78). I'll shoot you over some pics of how I modified mine.
 
Cr@p.. I think u are right. My body rear panels curve down a bit at the corners. I wanted the later '70s rectangular white/yellow/red tail lights. I'd rather not cut into my rig just to fit in tail light. Maybe I'll just go back to '71 round tail lights and bumperettes. Need to put some back up lamps somewhere, maybe other side of bumpers. I'll post pics or start my own thread later. Much thanks!! Please keep the tips and pics coming
 

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