tranny mount/crossmember- urgent help needed

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AuroraGirl

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Bolts undergo plastic deformation when torqued to a value that enables them to clamp with a lot of force

Bolts short of that, loose, will not hold tight and will loosen on their own
THe bolts return to the original shape when taken apart

TTY bolts build on this by going to the limit of what a bolt can plastically deform to , but it wont return when removed. Its got the most ability to hold for its size at that value, and its also easily replicated, it makes an OEM choose those depending on what they need

A bolt that has a larger span like those vs replaced with short ones allow them to get that clamping force, which they get more of with the spacer.
 
AuroraGirl

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Ricko1966 said:
CAFE stood for corporate average fuel economy, people tend to forget about this.The trucks had to average x mpg across the line. So without the hated 250s. 4.3s. and 305s to bring the average up no one would get a 350. And the 305s do just fine for everyday people doing average truck things just like thev283 2v did and save a few bucks on gas at the same time.
Click to expand...
Yes! esp with the 4.3 and the 4.8s people whine about from the gmt400+ eras
Admittdently, the only reason you could conceivably want a 4.8 in a early 2000s pickup when spec'ed beside the equivalent in a 5.3 was you would be without AFM...

The mileage was the same.
The 4.3 got a TINY bit better for city, and otherwise same. But i suppose 4.3 would be beneficial for fleet and for insurance costs(v6 vs v8 for those idiot companies)
 
SquareRoot

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Some science to convince myself this really is a thing. :pedobear:
 

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bucket

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bucket

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SquareRoot said:
3/4
Click to expand...

Something is amiss here. Because everyone else with a K10 or K20 has the crossmember below the frame. Well, except probably some that have been boon rigged.
 
Rustisbest

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Since there's 4 bolts, run 2 with spacers and 2 without. Bolts down on the short ones. Bolts up on the ones with spacers if it's 305 powered. All the bases should be covered.
 
SquareRoot

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bucket said:
Something is amiss here. Because everyone else with a K10 or K20 has the crossmember below the frame. Well, except probably some that have been boon rigged.
Click to expand...
I call Uncle @bucket, my mouth got disengaged from my brain. I just went out and had a look see. My bad. Carry on. However, I stand firm on ditching the cheesy spacers. Grade 8, 7/16 bolts have served me well.
 

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dragstews

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75 K15 Short Wheelbase Lifted 4 inches ...
Not sure what can of worms I got here ??

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Had a THM 400 in it using the stock crossmember with spacers between it and the frame rails ... Worked super well for 30 years like that ...

Whole new ballgame with installing the 4L85E trans now ...
Fixing to find out if this new gig will work as well .. ??
( Hoping there will be no need to call AAA to come and get my stranded bony butt !! )
 
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AuroraGirl

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dragstews said:
75 K15 Short Wheelbase Lifted 4 inches ...
Not sure what can of worms I got here ??

You must be registered for see images attach


Had a THM 400 in it using the stock crossmember with spacers between it and the frame rails ... Worked super well for 30 years like that ...

Whole new ballgame with installing the 4L85E trans now ...
Fixing to find out if this new gig will work as well .. ??
( Hoping there will be no need to call AAA to come and get my stranded butt !! )
Click to expand...
What is that block on each side made of? and nice , whod you get that aftermarket one from?
 
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Looks to be a Tejas Steelworks unit, have their 2wd unit in the 76 and it’s a nice piece.
 
dragstews

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AuroraGirl said:
What is that block on each side made of? and nice , whod you get that aftermarket one from?
Click to expand...
It is made by Tejas Steelworks .... I had to modify it for my needs ..

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Narrowed it so it would fit between the 4L85E trans and the NP203 transfer case ...

The spacers are made out of a solid block of aluminum ...

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You must be registered for see images attach


Driveshaft angle is spot-on ..
 
dragstews

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nvrenuf said:
How's the front? It should be worse but you may get by because of the low lift.
Click to expand...

Don't know yet ... Must add bout 3.5" to it ...
With having the CV joint and going longer should work pretty good without seeing much accelerated wear occurring ...

Old truck don't see much 4-wheel action .. Did convert the full time to part time so there's nothing spinning at highway speeds .. Unless the hubs are locked or the transfer case gets shifted into 4 lock ..

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Floor shifter works the TC, transmission is a column shift ..

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AuroraGirl

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dragstews said:
It is made by Tejas Steelworks .... I had to modify it for my needs ..

You must be registered for see images attach


Narrowed it so it would fit between the 4L85E trans and the NP203 transfer case ...

The spacers are made out of a solid block of aluminum ...

You must be registered for see images attach


You must be registered for see images attach


Driveshaft angle is spot-on ..
Click to expand...
Why are you using a solid block of aluminum? Aluminum is a lot weaker than steel, and its also going to cause corrosion against steel.
 
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