Rear end spongy after 4 / 5 static drop - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Fantom · 03-10-2013, 07:51 PM

I lowered my '71 LWB using 2" drop spindles & springs up front and 5" drop coils in the rear. I relocated the rear shocks and also installed the short shocks. The back is real bouncy, and when I drive down a rough road it almost feels like it's bouncing side to side as well.

I love the look, but hate the ride.

Has anyone else had this problem?
Will replacing the springs with bags stop this?

Thanks,
Kevin

Fantom · 03-10-2013, 07:52 PM

I know everyone loves pic, so....

**Hart_Rod** · 03-11-2013, 01:07 PM

Who's lowering kit? It seems that the CPP springs are "spongier" than the ECE ones that have purchased (at least in my experience).

**oldman3** · 03-11-2013, 01:32 PM

fantom, I had the same problem with a friends 67 LWB step side. I posted a thread #463544 about the problem. Since then I have changed the rear springs to what CPP called a 4"drop heavy duty spring. Didn't make any difference. We also changed the angle a little more on the shocks (more upright), no difference. The owner hasn't had time to work with me on more stuff, so it's still the same. Next things I wanted to check are angles on the pinion, two piece drive shaft, etc. If you can, read over my post and check out the pics, then post back here any more questions. Between that and your post maybe we can come up with a fix...Jim

**lolife99** · 03-11-2013, 01:48 PM

What brand shocks?

clemsonteg · 03-11-2013, 09:57 PM

What about the track bar?

tubbedII · 03-12-2013, 12:36 PM

I've seen the relocators for the shocks put on backwards...got a pic of them installed?

shawno72 · 03-12-2013, 12:37 PM

To me it sounds like your track bar may be running up hill

Fantom · 03-12-2013, 05:54 PM

Thanks for the replies. I feel real stupid now, because I figured out what the problem was.... I had the rear shocks on upside down. Flipped them over and problem solved.

Fantom · 03-12-2013, 05:57 PM

Quote:

Originally Posted by oldman3

fantom, I had the same problem with a friends 67 LWB step side. I posted a thread #463544 about the problem. Since then I have changed the rear springs to what CPP called a 4"drop heavy duty spring. Didn't make any difference. We also changed the angle a little more on the shocks (more upright), no difference. The owner hasn't had time to work with me on more stuff, so it's still the same. Next things I wanted to check are angles on the pinion, two piece drive shaft, etc. If you can, read over my post and check out the pics, then post back here any more questions. Between that and your post maybe we can come up with a fix...Jim

I hope your fix will be as easy as mine.

**oldman3** · 03-12-2013, 06:36 PM

Fantom, glad you fix was that easy. My shocks are on correct, hopefully within the next few weeks I can get with the owner, takes some more pics of track bar, springs, and check the pinion angle and then post up another thread for help from the suspension guys. I posted my first thread in the general area, got some info but didn't help with the problem...Jim

Gmforce · 03-18-2013, 12:16 PM

the panhard bar lenght and angle can affect this greatly as well ....fyi..

03-10-2013, 07:51 PM	#1
Fantom Registered User Join Date: Sep 2011 Location: Hattiesburg, Ms Posts: 65	Rear end spongy after 4 / 5 static drop I lowered my '71 LWB using 2" drop spindles & springs up front and 5" drop coils in the rear. I relocated the rear shocks and also installed the short shocks. The back is real bouncy, and when I drive down a rough road it almost feels like it's bouncing side to side as well. I love the look, but hate the ride. Has anyone else had this problem? Will replacing the springs with bags stop this? Thanks, Kevin

03-10-2013, 07:52 PM	#2
Fantom Registered User Join Date: Sep 2011 Location: Hattiesburg, Ms Posts: 65	Re: Rear end spongy after 4 / 5 static drop I know everyone loves pic, so....

03-11-2013, 01:07 PM	#3
Hart_Rod ************* Join Date: Apr 2005 Location: Pensacola, FL Posts: 17,835	Re: Rear end spongy after 4 / 5 static drop Who's lowering kit? It seems that the CPP springs are "spongier" than the ECE ones that have purchased (at least in my experience). __________________ Rob - https://www.instagram.com/hart_rod_c10 As Iron Sharpens Iron, So One Man Sharpens Another. Proverbs 27:17 FOR SALE: DBW pedal bracket - http://67-72chevytrucks.com/vboard/s...d.php?t=651123 FOR SALE: Hood Brackets http://67-72chevytrucks.com/vboard/s...d.php?t=679945 1987 Silverado SWB - 34.5K original miles http://67-72chevytrucks.com/vboard/s...d.php?t=801834 1969 SuperBurb - http://67-72chevytrucks.com/vboard/s...d.php?t=200387 1968 Farm truck - http://67-72chevytrucks.com/vboard/s...d.php?t=358692 1968 SWB - http://67-72chevytrucks.com/vboard/s...d.php?t=551258 1948 Chevy - http://67-72chevytrucks.com/vboard/s...=122164&page=3

03-11-2013, 01:48 PM	#5
lolife99 67-72 parts collector,… Join Date: Nov 2002 Location: Mid-MO Posts: 22,685	Re: Rear end spongy after 4 / 5 static drop What brand shocks? __________________ Keith Convert to disc brakes. http://67-72chevytrucks.com/vboard/s...d.php?t=444823

03-11-2013, 09:57 PM	#6
clemsonteg Registered User Join Date: Jul 2012 Location: Anderson,SC Posts: 953	Re: Rear end spongy after 4 / 5 static drop What about the track bar?

03-11-2013, 01:32 PM	#4
oldman3 Senior Member Join Date: Mar 2011 Location: West Plains, Missouri Posts: 7,555	Re: Rear end spongy after 4 / 5 static drop fantom, I had the same problem with a friends 67 LWB step side. I posted a thread #463544 about the problem. Since then I have changed the rear springs to what CPP called a 4"drop heavy duty spring. Didn't make any difference. We also changed the angle a little more on the shocks (more upright), no difference. The owner hasn't had time to work with me on more stuff, so it's still the same. Next things I wanted to check are angles on the pinion, two piece drive shaft, etc. If you can, read over my post and check out the pics, then post back here any more questions. Between that and your post maybe we can come up with a fix...Jim __________________ my build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=459839 Jimbo's long bed step build:http://67-72chevytrucks.com/vboard/s...t=464626<br />

03-12-2013, 12:36 PM	#7
tubbedII needs more $$$ Join Date: Mar 2004 Location: Sacramento Posts: 1,936	Re: Rear end spongy after 4 / 5 static drop I've seen the relocators for the shocks put on backwards...got a pic of them installed? __________________ 1970 2wd Blazer

03-12-2013, 12:37 PM	#8
shawno72 C/10 junkie Join Date: Nov 2010 Location: Stockton Ca Posts: 9,093	Re: Rear end spongy after 4 / 5 static drop To me it sounds like your track bar may be running up hill __________________ Shawn 70 LWB C10 current driver/project http://67-72chevytrucks.com/vboard/s...d.php?t=663051 68 SWB C10 Work in progress.....SOLD http://67-72chevytrucks.com/vboard/s...d.php?t=559520 72 LWB C10 Sold 71 LWB C10 Sold 68 LWB C10 CST Sold http://youtu.be/kbB0QrBIs9k My mom always had the best advice. It was just a tad late. After a fall that involved blood, she'd say....."Careful!"

03-12-2013, 05:54 PM	#9
Fantom Registered User Join Date: Sep 2011 Location: Hattiesburg, Ms Posts: 65	Re: Rear end spongy after 4 / 5 static drop Thanks for the replies. I feel real stupid now, because I figured out what the problem was.... I had the rear shocks on upside down. Flipped them over and problem solved.

03-12-2013, 06:36 PM	#11
oldman3 Senior Member Join Date: Mar 2011 Location: West Plains, Missouri Posts: 7,555	Re: Rear end spongy after 4 / 5 static drop Fantom, glad you fix was that easy. My shocks are on correct, hopefully within the next few weeks I can get with the owner, takes some more pics of track bar, springs, and check the pinion angle and then post up another thread for help from the suspension guys. I posted my first thread in the general area, got some info but didn't help with the problem...Jim __________________ my build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=459839 Jimbo's long bed step build:http://67-72chevytrucks.com/vboard/s...t=464626<br />

03-18-2013, 12:16 PM	#12
Gmforce Registered User Join Date: Mar 2013 Location: Pocatello Id Posts: 83	Re: Rear end spongy after 4 / 5 static drop the panhard bar lenght and angle can affect this greatly as well ....fyi..



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