lowered rear how far are you guys off the bump stops?

[rockytopper R.I.P 5-13-2017]

OK I made my first attempt at lowering the rear of my 55 nomad this weekend. I installed eaton 6 leaf 2 inch drop springs rated at 177 in/lb. I am a bit confused because I had read that a stock height trifive should have 5.75 inches between the top of the axle and the bottom of the frame rail. My nomad had 9.5 inches before I lowerd it and now it has 7.5 inches. I have 5 inches between the factory bump stop and the bottom of the frame. How far are you guys off the frame? I want to go down 2 to 3 more inches. I can play with removing leafs but I am considering installing blocks.
Thanks
Rocky

[JT56]

My car was 6 3/4 " from the top of the axle to the bottom on the frame. Its now 4".

[chevynut]

Mine is 3.75" from the frame with a 3.5" diameter halfshaft sitting level.

The stock height for a 55 would be 5.725" from the top of the stock 3" axle housing to the bottom of the frame at curb weight, and 3.625" at design load. It's in the assembly manual Section 3 sheet 5.

http://www.55-57chevys.com/tech/55/3-5.gif

This is why when people say their car is "lowered 3" I don't believe it without this measurement. Same with the front. "Dropped springs" can end up all over the place.

Do you have all the weight of the car simulated somehow? Without all the weight on the springs, you won't be able to tell where it's going to sit when finished.

[Maddog]

Is the wagon fully assembled? Sounds like your rear would be sticking up in the air at those measurements. Do not remove leafs, not a good thing to do. Blocks OK but no more then a 2" block, anymore and it can make taking a tire on and off very difficult. Are the shackles installed correctly?

[rockytopper R.I.P 5-13-2017]

The nomad is fully assemblied minus engine and trans, plywood rear deck, and tank of gas. None of which will make a big difference in the rear height. Changing tires is not going to be an issue on a nomad. Here is a comparsion of the leafs I took out and what I installed. Picture of car is after it is lowered. 2 inch blocks will put me about 5 inches from the frame to the top of the axle. I'm planning on running a 28.4 inch tall tire so the car will be going up another 1.2 inches from ground than shown with the 26 dia tire I have installed. I will gain some drop from engine but not much. My 200 lb buddy stood on the back bumper and it only went down 1/2 inch at the wheel opening.

L=http://s282.photobucket.com/user/rockytoppers1/media/IMG_9857.jpg.html]http://i282.photobucket.com/albums/kk243/rockytoppers1/IMG_9857.jpg[/URL]

http://i282.photobucket.com/albums/kk243/rockytoppers1/IMG_9868.jpg (http://s282.photobucket.com/user/rockytoppers1/media/IMG_9868.jpg.html)

[chevynut]

It's strange that the car sat so high with the stock springs when it should be at 5.72" with them installed. The new leaf springs have the same 177 lb/in rate as the stock 6-leaf wagon springs, but with that 2" drop built in. It should be sitting at 3.725" now with the new springs imo. I think I would be trying to understand why it's so high before making changes, or you could end up way too low. Try loosening the shackle nuts and front spring bolts to let the springs move freely and see if that helps.

I'd ditch the leaf springs and solid axle and go with an IRS and coilovers. :)

[chevynut]

Have you considered trying a stock sedan/HT 5-leaf spring? There are two spring rates that were used for them. The stiffer one is 144 lb/in.

[Maddog]

I don't see the rear seat. I think not having the car complete is definitely allowing it to sit high. You'll be surprised how much those things add up in weight, carpet, plywood, seats,tank, even trans.

[rockytopper R.I.P 5-13-2017]

We loosened the rear shakles last night and jumped up and down but no change. I will loosen the front and rear tonight and see what happens. I'm not sure the springs I removed were stock I had assumed they were lift springs from the axle meassurements I took before hand compared to the infor in the factory manual. Maybe I should check with Eaton to assure they sent the right springs.

[rockytopper R.I.P 5-13-2017]

Ok I just spoke with Eaton. Sounds like the problem is I need to force the shackles in the back position with weight off of car and then hold it there while someone lowers the weight back on the car. Its apparently a common issue they get calls about.

Rocky

[Rick_L]

Disregard what the "original" springs look like - they are nowhere near factory, and they sat VERY high. Notice the extra leafs.

I think you are very premature in assessing what the new springs will do - you need more components assembled onto the car.

[Maddog]

Yep, the car needs to be complete, the engine/trans will make a difference. use the springs you bought, proceed with the rebuild and then fine tune the drop with the blocks once the car is complete.

[chevynut]

Ok I just spoke with Eaton. Sounds like the problem is I need to force the shackles in the back position with weight off of car and then hold it there while someone lowers the weight back on the car. Its apparently a common issue they get calls about. Rocky

Are you saying your shackles are flipped forward instead of back? Of course that would cause a problem if that was the case.

[rockytopper R.I.P 5-13-2017]

Are you saying your shackles are flipped forward instead of back? Of course that would cause a problem if that was the case.

Yes that is the case.

[rockytopper R.I.P 5-13-2017]

Ok I'm back at square one. My shackles are installed just like the start of this thread. They do not appear to be flipped or need flipping.
http://www.trifivechevys.com/showthread.php/1081-Shackle-issues

[chevynut]

IMO your problem either that you have too stiff of springs, too much free arch in the springs, or not enough weight on them. If you think you have all the weight on the rear that it will see with your 200 pound friend sitting in the cargo area and it's still that high, I would change the springs rather than install blocks to lower it.

To lower your car where you want it, I think you should go with 4 (112 lb/in) or 5 (126 or 144 lb/in) leaf springs, perhaps even "reversed eye" springs, see where it sits, then add blocks if you need to. A 55 Nomad is only about 210 pounds heavier than a 55 BA sedan and part of that is the rear springs with the extra leaf.

What is the free arch on the springs with no weight on them? It's hard to tell in a pic. What is the arch when they are on the car with the weight on them?

Do you have a way to weigh the rear of the car? Clearly the engine, transmission, driveshaft, fuel tank, etc. are going to add some weight to the rear. Is the rear seat installed?

[chevynut]

you need more components assembled onto the car.

I agree. From what Rocky has said, he lacks is the rear plywood, fuel tank, and engine and transmission. The liftgate, side glass, bumper, and I'm assuming rear seat is there. What else is there of significance?

The stock engine and transmission is around 700-725 pounds, and probably 1/4 (if that) of it is carried at the rear wheels. A full tank of gas is probably 150 pounds with the tank included. The plywood may be 20 pounds. So something around 350-400 pounds in the cargo area should do it to simulate the completed car. But I'll bet it still sits too high. Total spring deflection should be about 1" when adding the 350-400 pounds to the cargo area.

[rockytopper R.I.P 5-13-2017]

I agree, I was about to point that out but you did the math for me. The missing engine trans and fuel weight aren't going to change things in the rear all that much.

[rockytopper R.I.P 5-13-2017]

I'm pretty certain now I was sent the wrong springs. Only way they aren't is if the nomads had a higher ride height than the advertized curb weight 5.72 dimenion between frame rail and axle. Else I have standard or lift springs installed. I'm on the horn with Eaton hopefully we can figure it out.

[rockytopper R.I.P 5-13-2017]

Ok problem solved. They sent me 2 inch lift springs not 2 inch drop spring per order. If they make it right all will be well.
Rocky

[chevynut]

I guess they wanted to drop the axle, not the car. LOL!

Glad you got it sorted out. So it should drop 4" from where it is now if they're really 2" dropped springs.

[rockytopper R.I.P 5-13-2017]

Turns out they sent me standard height springs. So I'm going to have them send me 3 inch drop this time which will put me at approximately 4.5 inches from axle to bottom of frame. Adding the missing weight and spring settling should give me a true 2 inch drop form oem with the heavier rated springs.

[NickP]

With a pair of 2" ratchet straps, you should be able to pull the body down to the appropriate distance, then tighten the fasteners to the proper torque values that way, you wouldn't have to stack a bunch of weight in the back end.

[rockytopper R.I.P 5-13-2017]

I'm 6 inches down from start currently 3.75 inches from axle to frame.
This was a 6 leaf 3 inch drop spring second go around.
Rocky
http://i282.photobucket.com/albums/kk243/rockytoppers1/image-33.jpg (http://s282.photobucket.com/user/rockytoppers1/media/image-33.jpg.html)