axle over spring on '53 3600 frame?

[53farm]

Is anyone running a rear axle flip (spring-under-axle) on a 1947-1954 Chevy 3600 WITHOUT a frame notch?

I have a rear axle out of a 90's blazer that I want to install on top of the leaf springs to drop the rear down a bit. I know the perches will have to be changed. I also know notching is ideal for max travel but not sure I'm at the point of wanting to cut the frame. Not looking to lay the frame on the ground obviously, but hoping to do a 4" dropped axle in the front and would like the rear to end up about the same height as the front. From what I understand, the 3100 frames have a taller arch in the rear than the 3600 frames, and wondered if anyone is running the spring-under-axle configuration with no notch on a 3600 truck? If so, does it still have a reasonable amount of suspension travel? Truck will be a driver/cruiser/occasional mild hauling. Thanks.

[_Ogre]

i thought the ad trucks already ran the axle on top of the springs.

[53farm]

The 1/2 tons are indeed spring under axle, but the 3/4 and 1 ton truck are spring over axle in stock form. Was doing some more searching, looks like flipping the rear shackles upside down may be a possibility, but still curious to hear from anyone running their rear axle on top of the springs on a 3/4 ton 3600 truck.

[Hogger54]

I don't think your going to have much room without a notch. I pulled 3 leafs, and put a mustang axle in. I'm at 4" from the bump stops with the axle below the springs.

[Hampshire]

If you flip the axle to the top, you have 3" or less - not enough. I'm doing a 2" notch on my 3600 in the next week or so. I've already removed some leaves and will be doing a couple other tweaks. Definately easier to lower a 1/2 ton.

[OrrieG]

this might help a little, show stock relationships
http://chevy.oldcarmanualproject.com...esto/53134.htm

[mr48chev]

I'd think you will need at least a 2 inch notch if you flip the axle just for movement clearance even if you never carry a load in it.

Flipping the rear shackle even if it will flip will throw your pinion angle off a bit at best and I'd imagine that raising the spring hangers to lower the rear is far more work than putting the axle on top of the spring and putting a mild notch in and boxing that section of the frame.

[Coach529]

Here is a picture of a axle flipped and a notch on a 3600 frame.

[53farm]

Thanks for the replies folks!

[2or4wheels]

Originally Posted by 53farm

Is anyone running a rear axle flip (spring-under-axle) on a 1947-1954 Chevy 3600 WITHOUT a frame notch?

I have a rear axle out of a 90's blazer that I want to install on top of the leaf springs to drop the rear down a bit. I know the perches will have to be changed. I also know notching is ideal for max travel but not sure I'm at the point of wanting to cut the frame. Not looking to lay the frame on the ground obviously, but hoping to do a 4" dropped axle in the front and would like the rear to end up about the same height as the front. From what I understand, the 3100 frames have a taller arch in the rear than the 3600 frames, and wondered if anyone is running the spring-under-axle configuration with no notch on a 3600 truck? If so, does it still have a reasonable amount of suspension travel? Truck will be a driver/cruiser/occasional mild hauling. Thanks.

I didn't want to cut on my frame either, but ended up doing it. A buddy of mine came over to do the welding as I didn't quite have the confidence to make good welds on something so critical. Picture attached. Have a Camaro/T.A. rear under it now, removed 2 leafs. There was another guy on a different forum that put a Progressive kit under his 3600 (http://www.progressiveautomotive.com...uspension.html). I didnt go this route, because it seemed that the leaf packs would be sitting too close together for our ~40" frame width. But it appears it can be done.

[DaveCt]

I just completed my notches this past weekend.

[Coach529]

Originally Posted by DaveCt

I just completed my notches this past weekend.

Looks great!!

[DaveCt]

Originally Posted by Coach529

Looks great!!

Thanks Coach. Your build thread was an inspiration, thanks.

[1948GMC]

Ya notching works best I am going to have to do that to my 3/4