Does lowering change drivetrain mounts?

[olskool68]

Hey folks, getting to the point where all my major pieces (engine, tranny) are getting wrapped up but I have a question. I've installed a 3" CPP drop axle and 3" drop mono's on the front. Not sure yet what I'm doing to get the rear that low (Flip vs reverse eye mono).

The engine is a 235 but we are going with a 200 4r tranny so the mount will be a crossmember from CPP. Does a static drop of 6" or more change how the tranny will sit if I'm using the original motor and motor mounts? Or can I just buy the crossmember and call it safe? In most cases, I see that changing the spring pads on the axle happens so is the pinion angle different when lowered?

Thanks guys. This is my son's 58 Apache fleetside.

[NEWFISHER]

Not unless you are laying frame and need to "tuck" the trans/driveline etc. When you hang the 2004r from the adapter and set the cross member, make sure the tail shaft is at 3 degrees down. I used a non-ratchet tie down looped over the frame rails and hung the tailshaft high. I shortened the ends of the crossmember to fit inside the rails and then bolted it to the trans. Lowered it down while watching the degree gauge until it rested at 3 degrees and tacked in the cross member. You also want the rear pinion measured at flange up 3 degrees.

[olskool68]

Originally Posted by NEWFISHER

...make sure the tail shaft is at 3 degrees down. I used a non-ratchet tie down looped over the frame rails and hung the tailshaft high. I shortened the ends of the crossmember to fit inside the rails and then bolted it to the trans. Lowered it down while watching the degree gauge until it rested at 3 degrees and tacked in the cross member. You also want the rear pinion measured at flange up 3 degrees.

Thanks for the reply. Is it best to have the frame level on stands before making the degree adjustments?

[98layinframe]

You want the vehicle sitting close to its normal ride stance that way the motor will be sitting at 3° while driving.

Also since its a leaf sprung vehicle, your gonna want to set the rear pinion at 2° instead of the normal 3° only to help compensate for the axle wrap associated with leafs when under throttle.
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[dubie]

I have the same axle and leaf drop up front as you and I'm running 6" reverse eye mono's on the back. I set my pinion angle on my diff at 2 degrees up and the tail shaft at 3 degrees downward.

Did you install any caster shims up front? Once you lower it that far you need to re-adjust your caster. I bought a 6 degree shim kit from Performance online

[_Ogre]

the mounts are basically the same, but...
the trans mount is about the easiest thing to fabricate on your truck
why buy a piece of pipe?

[mechanixman]

Maybe this will help
http://jniolon.clubfte.com/driveline...nephasing.html

[olskool68]

Originally Posted by dubie

I have the same axle and leaf drop up front as you and I'm running 6" reverse eye mono's on the back. I set my pinion angle on my diff at 2 degrees up and the tail shaft at 3 degrees downward.

Did you install any caster shims up front? Once you lower it that far you need to re-adjust your caster. I bought a 6 degree shim kit from Performance online

Did you flip the axle or just go with the mono's? I did install the 6 degree shims. i was going to go with the 4 but read enough on here where 6 was what most folks agreed on.

[dubie]

i used a set of reverse eye mono's in the rear to drop it 6 inches to match the drop in the front

[olskool68]

Thanks for all the replies, gents. I decided to go with the flip kit and adjust from there.

[sqrlnts]

I noticed with mine (very similar to Dubies setup) that the center frame cross support above the trans tailshaft is very close (~1/2") to the driveshaft. I have had no problems with it contacting but I don't have a bed floor. This may become an issue for me once I try to haul a load, if that day ever comes.

[butchp]

I would get the rear setting where it is going to be berore I tried to set any angles.

[olskool68]

Originally Posted by sqrlnts

I noticed with mine (very similar to Dubies setup) that the center frame cross support above the trans tailshaft is very close (~1/2") to the driveshaft. I have had no problems with it contacting but I don't have a bed floor. This may become an issue for me once I try to haul a load, if that day ever comes.

That's the kind of advice I need to hear! Thanks. I'll watch for that.