Trans Crossmembers

SSchmi5519

LLY Cult Leader
Oct 19, 2008
3,387
1
36
Arizona
Dimple dies for the win. Look trick as heck, save weight, and keeps the section strong. You can buy them individually.
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,610
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Mid Michigan
Tom, reducing weight is something I'm working on now, I've already reduced the thickness on everything but the base plate and I know that will help allot. The stock cross member weighs 22 lbs. and my prototype weighs 36. The production model will weigh allot less, hopefully in the 20's. GM did an excellent job building a strong light member. Cutting windows in strategic places is a great idea and I'll defi look into. It will increase my cost, I pay by the inch on cuts. I'll get a price on it, if there are people willing to pay the actual cost passed down to me I have no problem doing it. I'll try to get something drawn up this weekend.

Thank you for understanding where I was coming from.

Have you looked into tubular Metals with mounting and base plate to see how it compares Landon?
This was what I was getting at originally. If Brian ever looks in here again, maybe he could weigh that extra one he has and then we can compare?

Dimple dies for the win. Look trick as heck, save weight, and keeps the section strong. You can buy them individually.
Nice idea! Like this?
images

Cheese o/swiss anyone???
 

LWATSON

future trans limpers
Jul 30, 2008
2,587
1
36
55
Scotland Neck NC
Just wanted to give an update, the cross member won't fit 5 speeds because the shift linkage is lower and in the way. It seems people are more interested in weight than anything. I'm going to build a second prototype using a piece of rectangular tubing as the main support. Hope everyone isn't loosing interst, I hope to have the new prototype ready in a few days.
 

TeaBagger2006

Im a Garrett Nut Swinger
May 11, 2008
3,123
15
38
Bis ND
I was under my truck and noticed how close the linkage is....I even told myself to post about it on this thread....I forgot
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
Zfs cross members are different, I'm gonna build my own because it's actually bent up pretty bad from when ot was a co-op truck. With bolted engine mounts how much torque do you think the trans crossmember is seeing?
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
My brothers trans mount seperated completely, and he ran it at the strip without knowing, low 14s truck same truck as mine but basically nothing done to it other than efi. His trans actually slid over and dented the floor over where the shifter comes through the floor, and dented the tunnel out where the case was hitting from the underside. he literally had nothing holding the trans down at all. Just holding it from falling on the ground lol. He was dumping it at probably around 2200 rpm as he only runs a single disc clutch. So with literally nothing holding the trans from torqueing over. it didn't really change anything that was with non bolted engine mounts.i don't thing the torque made it dent the floor and tunnel I think that was just from the trans vibrating over into the floor.

On the other hand my truck had smoked engine mounts allowing my engine to torque over so bad on a launch that the front drive shaft was Hitting the rear engine plate and dug a nice notch into it. I'm not saying no torque load goes through the trans crossmember I'm just saying I don't think it's alot, I mean the trans is only mounted to it in the center I doubt the mount is physically capable of transferring any massive kind of load anyway.
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,713
775
113
Texas!!!
Landon, I just noticed this thread is still in the SoCal section. I'm going to go ahead and move it to Evan's section since you are working with him on selling them.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,670
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Phoenix Az
Zfs cross members are different, I'm gonna build my own because it's actually bent up pretty bad from when ot was a co-op truck. With bolted engine mounts how much torque do you think the trans crossmember is seeing?

ALOT. my old NBS 2000 1500 with a 4.3 and nv3500 liked to eat motor mounts and killed my trans crossmember/mount. apparently hitting 3ft-4ft whoops at 45mph for a few miles is pretty hard on that shit even with long travel suspension :rofl:
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
ALOT. my old NBS 2000 1500 with a 4.3 and nv3500 liked to eat motor mounts and killed my trans crossmember/mount. apparently hitting 3ft-4ft whoops at 45mph for a few miles is pretty hard on that shit even with long travel suspension :rofl:

Lol I guess I was talking more for street application. But what about with bolted or poly engine mounts, wouldn't that keep the engine from torqueing as much therefore putting a huge stress relief on the trans mount? That's the other thing, the torque it does see the mount probably eats it up instead of the crossmember itself?
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
And a sled puller might be a different story, but if we're talking about a lighter crossmember I figure were leaning towards street trucks, but the extra clearance would benefit a off road truck or lowered truck obviously to.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,670
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Phoenix Az
Lol I guess I was talking more for street application. But what about with bolted or poly engine mounts, wouldn't that keep the engine from torqueing as much therefore putting a huge stress relief on the trans mount? That's the other thing, the torque it does see the mount probably eats it up instead of the crossmember itself?

nope. you dumping the clutch is a great replay of hitting whoops at the speed i was going. rear end off the ground, tires speed up, tires slam next whoop, tires slow dramaitically, then repeat. you slamming the clutch engaugement which is the engine spinning up and then dramaitically slowing down when the clutch catches, power still has to go somewhere (and it aint always tires) and the squishy trans mount will be the next to eat it. you have rotational forces trying to push the trans one way or the other. kinda like a helical gear cut creates torsional load in a trans. the engine mounts are so far forward, they can only stop so much movement.
 

zf>allison

you never had your car.
Apr 30, 2013
3,394
0
36
elsberry mo
I guess I just know how much my engine torqued before and after I bolted my mounts, I understand what your saying James for sure. I guess I just figured with better engine mounts you could get away with a lighter duty crossmember.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,670
5,818
113
Phoenix Az
I guess I just know how much my engine torqued before and after I bolted my mounts, I understand what your saying James for sure. I guess I just figured with better engine mounts you could get away with a lighter duty crossmember.

you can certainly get away with a light crossmember, just depends on your materials and design. Landon will get it dailed in and improve on it. its all part of R&D

Same reason the traction bars i use to build weighed 60lbs total (thats mounts, joints, bolts, everything together and both bars together) where others were twice that weight but were just as strong or stronger. Also why guys told me you could never run a coilover on these truck, let alone a stock height truck. where there is a will, there is a way. just takes time!
 

LWATSON

future trans limpers
Jul 30, 2008
2,587
1
36
55
Scotland Neck NC
Still working on this, the prototype fit an LMM but not LBZ,LLY AND LB7. Been busy with other projects also so it's tough to juggle time around. Sorry for the delay!
 

TheBac

Why do I keep doing this?
Staff member
Apr 19, 2008
15,610
1,866
113
Mid Michigan
Still working on this, the prototype fit an LMM but not LBZ,LLY AND LB7. Been busy with other projects also so it's tough to juggle time around. Sorry for the delay!

NO big deal. Thank you for taking the effort.