Technical Caution for drivers using Auto restorations T5 Kit

Should have read 10 years

 

One other thought on this subject. The rear suspension is dependent on a u joint on the torque tube so the entire rear driveline swivels on a center point. The engine and transmission have to be solidly mounted to the frame in order for this to work. I'm using Float-A-Motor rear engine mounts and a '32 front motor mount with rubber biscuits. Also using the S-10 rubber trans mount. So, I have a certain amount of flexibility in my driveline that the OP may not of had.

 

The rear axle turns/swivels around a center point (approximately the driveshaft) as the wheels go up down over bumps, frequently one at a time. Your front mount will not "turn" axially when that happens. It will only allow the wishbones to rotate up and down as the whole rear axle bounces. The thing in your suspension that is twisting during a one-sided bounce is the metal in the wishbone (actually separate hairpins now that just happen to be bolted to the same front mount). I think that you are in the group of hot rodders that are lucky so far. But bound to break once the stress point is reached.

 

This makes a lot of sense, but when you lift your axle 6 inches, on one side that will make the bolt turn about 15-20 degrees (this is only ball park numbers, and migth be over the top but you get the point), and that will make your engine rock like a boat every time you hit a pothole.

I know and understand they can survive a lot of use and abuse.
And so you have proven.

I don't doubt that you thought it true, but if a major component in the rear suspension fails that's a bad thing! These bones fail, and that can happen to others.

And if this is used and installed the wrong way or can lead to bad things. I would never be happy with a bolt in such a critical position without some kind of bushing around it, so it dosent wear the bolt out and leads to failure.

Although I like the basic setup, I think they cheaped out on the pivot point!

 

It has been repeated many times, when you split wishbones you effectively create a giant anti-roll bar out of the rearend housing. Since the rearend housing does not really move much, the deformation is taken up by the radius rods, and is worse when one wheel hits a bump such that the rearend becomes tilted vs the frame of the car.

Now back to the OP, having the poor quality welds on the "heavy duty" radius rods is really the main problem here. They are mounted fairly close to the center, which minimizes the anti-roll bar effect. Still not preferred geometry though. Having rubber mounts in the engine and trans would certainly help vs solid-mounted as denis4x4 pointed out.

 

No disrespect intended, but I don't agree that the "poor welds on the heavy duty arms" are the main problem.

The real problem is like many pointed out, the arms that mounted like that with a bolt, is causing a twisting effect to both arms when one wheel moves up/down, or during body roll.

If a person chooses not to go with a center ball mount which would fix it correctly, then beefing the bones/arms or using tubing arms/bones is the opposite of what should be done in bone construction. ...The bones should rather simulate the 60-72 Chevy truck arms "cross-section". Those are two pieces of stamped steel, C or U shaped channels, riveted back to back. This makes an I or H profile, which allows them to be very "twistable". Then there are no dramatic forces applied to the bone, or front and rear attaching points.


Back to what Alchemy disagrees with the statement from Dennis, about not showing any deflection... I agree with Alchemy; We can prove that there is excessive loads to that front pivot point. Remove that big bolt and use a 6" long 3/8" carriage bolt, just to keep things lined up. But leave that extra long bolt with lots of free space on either side of the two arms. Now jack up one wheel a lot, and that bolt will bend to a lazy Z shape. That would show, or prove, that there is a twisting force on both arms as one wheel lifts, or drops.

So I need to ask why anyone would be reluctant to simply redo the front mount, add a simple crossmember to be able to use a Model A or V8 front bone yoke and ball socket.


It seems a bit odd to me that some would try to fix that poorly conceived mounting, by allowing the motor and trans to get moved by the bones being twisted. As I've said, a simple change to a center ball seems so obvious, as a cure.
.

 

WTF is that?

 

Here's a fix to the problem with this front mount. Remove the big bolt at the front of the wishbones and put a heavy-duty Heim joint in between them. Screw a bung onto the end of the Heim and swing it up between the sandwich plates mounting off the bottom of that trans (may need to notch a little from the sandwich plates). Weld the bung in there nice and solid. Now the wishbones can articulate just like the original clamshell did.

 

Disclaimer : this post may contain sarcasm in its highest form.

Of course the rear end of it busted off -

and thats because there's a huge problem at the front mount. The peepee little tab at the front, and the peepee little bolt at the front broke the 1/2" plate sleeved into and welded to the tube.


This is major wrong

(This is probably a close representation to the OPs set up even though it belongs to Dennis )

Because it broke this.



All this talk about the rods mounting at the front and the rear articulation, doesn't a stock setup articulate the same?


Any chain will break at its weakest link, any radius rod will break at the highest stressed point or weakest link
yep the peepee tab and peepee bolt.

 

on a stock set up the "ball" at the front of the torque tube can rotate. the rods bolt to the torque tube........oh wait........sarcasm

 

But the torque tube is the key to the entire system working. The tube is a multi faceted player, Once the torque tube is removed the entire game plan changed and all facets need to be covered.

 

Damn you, auto correct and fat thumbs. And thank you prime is not a crime. I corrected it.

 

I agree with you up to the point of, that the bad thing is not the weld broke, be that we have a problem that leads up to the weld on the bones breaking.

But he can thank god/faith/chance/luck he was at highway speed going almost WOT, because then sombody else would be telling us about this!
Imagine the front pivot point braking and digging in to the ground. Not a good thing. But this made them break at the point where it would drop down and slide to a screening hauled.

 

can we not run the 39 trans with 44/47 gears behind a banger with a lite flywheel and have fun....?

 

Just jumping into the conversation:

1) The radius rods (though triangulated to the front) have no mechanism to articulate at the front. There is no mechanism for each rod to twist if only one side of the rear end goes up or down. So, the load/twist is all transferred to the rod itself - so the weakest point fails.
2) The design is the problem - the front mounts are causing undue stress on the whole radius rod ***embly - bolts included.
3) Triangulated setups like Pete and Jakes use rubber lined rod-ends up by the ****** - the rubber can flex and absorb the challenge of one wheel being higher/lower than the other.
4) Welds: The weld was the weakest point in this particular setup - so it gave first. With that said - the weld had very little heat penetration into the heavy underlying bracket - so it easily broke (just looking at it, you can tell it was a big problem). Notice all the rust in the area - I'll bet it was cracked and ready to fail for a long time.

It is hard to weld 1/8" material to heavy material like the backing plate bracket - preheating the heavy material would have helped. The weld that is shown is very 'cold' and was not in any way properly done. Having some rosette or plug welds on the side could have helped - but only if there was enough heat penetration into the thick/underlying material. I would have pre-heated the thicker material and made sure I had enough amps on the welder to cause the heat penetration required for a structurally solid weld. Welding this thing cold - makes it a very difficult situation.

This setup can easily be fixed - with a bit of fabrication in the front and some good welding skills in the rear. Me - I would TIG the thing . . . only after I used a rosebud oxy/acet torch to heat it up.

 

The best of all worlds is to use the T5 UNMODIFIED and KEEP the torque tube.
Between the HAMB and Fordbarn I have probably posted the fairly easy solution
with pics at least 3 times.
You will have to search for it this time.

 

I never knew aluminium gearbox castings were meant to be suspension mounting points. Especially with a twisting force applied.

 

My head hurts.

Engineering is not a guessing game.

Who sells this ****?!

 

I got one of these kits from a guy used and immediately saw the poor workmanship and design. Looks look it was done by a 10 year old under a Shade tree. Not only is there no pivot point for the radius rods but the mounting is way lower than stock, twisting the shackles. Can't believe he sold the kits for $1000????

 

Appears to be no penetration to heavier bar from weld ( pic 2 ). See comment in post 8.

Plus all the other problems from incorrect geometry.

 

There's no need to preheat that heavy iron. The weld need is to set the amps right and that the **** be clean. A small dig into the bigger stuff at the joint will help too, rosette welds need to be more like sunflowers. Bigger diameter, a hole partially drilled in the heavy to fill up as you work your way to the outside. I'd bet my 39 Ford it wouldn't fail. Next the front has to float as Henry designed it to. The tunnel vision engineering was seeing up n down only, no considerations further. The comment earlier about restoration folk not knowing what they're doing? I was going to get into a dissertation of sorts but I think a simple "...**** off..." works just as well. That's coming from a 43 year restoration type who knows that most are looking for lower revs vs higher speed. Just sayin. I'm glad that not only the O/P posted this for others but as was said, glad it happened when it did and not at "...70 MPH..."

 

There are two issues here:
1. The failure of a part supplied in a kit; and
2. The attachment points for the wishbones.
Having done business with Automotive Restorations, I can relate to the poor fit and finish of their products.
On the subject of the wishbone mounts, I have mixed emotions. As one poster put it, I'm lucky that I haven't killed anybody yet! On the other hand, this has worked for me for 10 years and thousands of miles. I'm leaning towards something that has two Heim joints attached to the rear of the transmission that will allow each wishbone to articulate individually. I suspect that if I were running a SBC or other high HP engine, I would have seen problems with this set up a long time ago. Since it snowed last night, I can go into winter rebuild mode and figure this out between now and spring. I do appreciate the input.

 

You guys are funny



Personally I can't tell what the weld looks like from here, so neither can you.

What you can see is that the weld is still on the Heavy plate & that its broke off at the tube. Soooo the lack of penetration into and preheating of the heavy plate ,,,, looks like the weld ripped at the tube and is plenty well dug into the plate. Very well may have been that the weld was run too hot for the 1/8 tube material to take.

You also can see some kind of metalwork was done to that tube and its under the paint. No clue what it was but something happened. Was it plug welded, was it repaired once before, I won't speculate but I'm sure someone will.

Look at the rust , both top and bottom yet its shiny and fresh throughout the center. That tells me (and should you) that the thing was fractured for a while. With the highest stress or weakest parts on the top and on the bottom.

 

I commend you for seeing the potential problem and looking for a solution to the situation instead of just running on a history of luck. Good Job!

 

I personally think that there is undue stress put on the tailshaft housing of the T5 which is cast aluminum with that design, and we all know that cast aluminum doesn't fracture or break. Those lower mounting bosses on the tailshaft housing were designed as anti-chatter rod mounting points for the trans. I would be looking at a crossmember mounting alternative for the bones pivot point and standard tierod ends with bungs welded in the bone ends, or heims.

 

Lucky and others are right....the whole thing is in a bind, the axle cannot move. And attached to the aluminum tail housing......ok.....rite. Stupid. You have to have a heim or ball type connection, bolted ***e, with appropriate spacer(s) or it will certainly break. Even on a ladder bar set up, on the street you have to watch going on off canter surfaces, it will bind ansd stress the heims. You have to constantly inspect and check to ensure no stress probs leading to failure. And those welds, **** obviously no experianced. Lucky the front didnt break and pole vault ur azz off the road

 

i cant possibly see how anyone who has the ability to install that **** would bother putting it in anything but the dumpster ,I know its a bit different than a set of 1935 radius rods but ! we have been using them for ever, with 9in ford diffs driven by screaming small blocks with front radius rod pivot balls welded threw the tubes CORRECTLY and cups and a extra link from just behind the pivot ball to top of 9in housing to prevent rotation and no problems one 35 has been together since 1975 still going strong and running hard some times ,then this mess ****s itself after 1200 miles with a banger motor ,sorry for the rant

 

This is what Pete was talking about. There is another member doing a clamshell attachment on the back of a T5 from a 4x4. Crazydaddyo

 

"Loudpedal"on the HAMB also made a similar setup with a Jeep T5 and a clamshell he cast himself. Pretty neat setup. All of these are a better and safer setup in the long run.

 

Please explain that first setup?? From what little is shown, this can't work right; as the rear end moves up/down, it will "lever" the trans tail up, using the torque tube ball mount as a fulcrum.