Jump to content

How do you know when shocks are shot?


jeffw

Recommended Posts

We're out for our first trip this weekend and I'm wondering if we need new shocks. The truck has 735k on it and we didn't get any service records with it. We did replace the cab shock absorber and stay rod when we bought it last year.

When we go over really bad bridge joints the cab tends to oscillate a few times before it settles down. 

Thoughts?

2007 Volvo 780 Volvo D12D, 465hp, 1650 ft/lbs tq., ultrashift

Link to comment
Share on other sites

#1: Are they leaking?
#2: You would need to take one end off and check if the still have damping or if there is radial play.

It would be good to know what a new shock feels like before you get the wrenches out

"There are No Experts, Do the Math!"

2014 Freightliner Cascadia DD16 600hp  1850ft-lb  18spd  3.31  260"wb
SpaceCraft S-470
SKP #131740

Link to comment
Share on other sites

Since you replaced your cab shocks recently, just get used to the cab rocking a bit.  It's normal.

Did you stay tandem?  If tandem, I would only replace one set of shocks.

If not tandem, you might want to replace that set now if you don't know how old they are.

Rocky & Sheri Rhoades
'01 Volvo 770
2016 DRV Mobile Suites, Houston
HERO Makers Ministry

 

30495168531_143d8fb8d6_m.jpg

Link to comment
Share on other sites

Change them!  Shocks do not last long on these "Big Toys"  If you are going to remove one to "check it out" why not change them while you're there.  Replacement OEM shocks are available from various sources and are not very expensive.  New shocks do make a difference in ride quality just dont expect it to ride like your Chevy.  

You also didn't happen to mention if you have an air ride front suspension. If so look at the air bags and the leveling valves for proper operation and ride height.  Suspension bushings may need replacement.  Cab bushings don't last forever. Lots of parts wear on these trucks and are never replaced by the previous owner(s). A big problem with no maintenance records is no "base line" exists to see if parts were ever replaced. 

Link to comment
Share on other sites

Good suggestions...thanks.

We are tandem, and it has air front suspension. Shocks weren't leaking last time I looked...will put eyes on them again. They were Volvos, which makes me wonder.

2007 Volvo 780 Volvo D12D, 465hp, 1650 ft/lbs tq., ultrashift

Link to comment
Share on other sites

If you pull one, change it. Takes big wrenches or a good air wrench (not a harbor freight. Mine was not powerful enough) and I ended up cutting one bolt off with a reciprocating saw because the bottom bolt was seized to the bushing.

 

Brad 

Brad and Jacolyn
Tucker the Wonder dog and Brynn the Norfolk Terrier
2009 Smart "Joy"
2004 VNL630 "Vonda the Volvo"
2008 Hitch Hiker 35 CK Champagne Edition
VED12 465 HP, Freedomline, 3.73 ratio, WB 218"
Fulltiming and loving it.

 

Link to comment
Share on other sites

I would preemptively change them. And it may be time anyway. That way you know what you have, and they are not expensive, and are generally pretty easy to change. If you have front air suspension make sure the bags are functioning properly. You will get some sway int he cab - that is normal. It is hard to say what is excessive from just a description. But I'd change the shocks since they are an unknown and cheap.

Jack & Danielle Mayer #60376 Lifetime Member
Living on the road since 2000

PLEASE no PM's. Email me. jackdanmayer AT gmail
2016 DRV Houston 44' 5er (we still have it)
2022 New Horizons 43' 5er
2016 Itasca 27N 28' motorhome 
2019 Volvo 860, D13 455/1850, 236" wb, I-Shift, battery-based APU
No truck at the moment - we use one of our demo units
2016 smart Passion, piggyback on the truck
-------------------------------------------------------------------------
See our website for info on New Horizons 5th wheels, HDTs as tow vehicles, communications on the road, and use of solar power
www.jackdanmayer.com
Principal in RVH Lifestyles. RVH-Lifestyles.com

Link to comment
Share on other sites

If you don't have to fight rust, figure about $75 each and 5 minutes to replace the front ones with a good impact wrench.  No need to jack it up, take off a wheel, or anything like that--just open the hood.  Just like the shocks on a car, every 100,000 miles or so a new set will make a difference.

If I had a rusty truck, I might be tempted to leave them alone.

45' 2004 Showhauler -- VNL300, ISX, FreedomLine -- RVnerds.com -- where I've started to write about what I'm up to

Headlight and Fog Light Upgrades http://deepspacelighting.com

Link to comment
Share on other sites

2 hours ago, Nuke-E said:

If you don't have to fight rust, figure about $75 each and 5 minutes to replace the front ones with a good impact wrench.  No need to jack it up, take off a wheel, or anything like that--just open the hood.  Just like the shocks on a car, every 100,000 miles or so a new set will make a difference.

Are the rears that easy too?

2007 Volvo 780 Volvo D12D, 465hp, 1650 ft/lbs tq., ultrashift

Link to comment
Share on other sites

When I built my off-road truck, I measured what I wanted for the limits of full open, full close, and normal position, and then seached through a couple different web sites and found the shocks I wanted. The measuring was the longest part and the searching was quite easy.  In your case, since you have an existing shock and the ability to get a part #, just see what the specs are for your existing shock and buy one that matches/exceeds.

Link to comment
Share on other sites

7 hours ago, Refuzn-To-Grow-Up said:

How do you go about buying the correct shock (Monroe or other brand)?  I am guessing my local auto parts store does not have a cross-referenced chart for a Volvo.

 
 

Shocks pretty much go by Generation on our trucks.  Class 8 truck parts is great to deal with as well.  Do a search on their website and your part numbers appear.  You can cross reference the part numbers.  Or your local HDT supplier should be able to work off of the last 6 of your VIN number.  NAPA can usually find them.

Alie & Jim + 8 paws

2017 DRV Memphis 

BART- 1998 Volvo 610

Lil'ole 6cyl Cummins

Link to comment
Share on other sites

8 hours ago, Refuzn-To-Grow-Up said:

How do you go about buying the correct shock (Monroe or other brand)?  I am guessing my local auto parts store does not have a cross-referenced chart for a Volvo.

I haven't looked for shocks specifically, but NAPA does have heavy duty truck listings (on a clunky website), and O'Reilly's has HDTs in their catalog (good website, but probably not as extensive of part offerings).

45' 2004 Showhauler -- VNL300, ISX, FreedomLine -- RVnerds.com -- where I've started to write about what I'm up to

Headlight and Fog Light Upgrades http://deepspacelighting.com

Link to comment
Share on other sites

The existing shock absorber has a part number on it likely. That number will cross to other manufacturer models that will fit. I wouldn't be afraid to source this at an Amazon or Ebay, as long as the product being purchased is a recognized name brand. 

One of my favorite sources of HD truck parts:  https://www.ryderfleetproducts.com/ryder/

 

 

Jeff Beyer temporarily retired from Trailer Transit
2000 Freightliner Argosy Cabover
2008 Work and Play 34FK
Homebase NW Indiana, no longer full time

Link to comment
Share on other sites

34 minutes ago, beyerjf said:

The existing shock absorber has a part number on it likely. That number will cross to other manufacturer models that will fit. I wouldn't be afraid to source this at an Amazon or Ebay, as long as the product being purchased is a recognized name brand. 

One of my favorite sources of HD truck parts:  https://www.ryderfleetproducts.com/ryder/

 

 

Jeff:

I just checked out this website.  Excellent resource.  THANKS!

Link to comment
Share on other sites

Hi Everyone,

I have a question about shocks myself. What shock would work best for are application. Volvo brand, I believe is an oil filled shock or a shock like a Monroe which I believe is a gas shock ?

All opinions welcomed,
Al

2012 Volvo VNL 630 w/ I-Shift; D13 engine; " Veeger "
  Redwood, model 3401R ; 5th Wheel Trailer, " Dead Wood "
    2006 Smart Car " Killer Frog "
 

 

Link to comment
Share on other sites

A gas shock still has the conventional oil damping valving, typically 50-50, meaning the valving is set to be equal on extension and compression . Add a compressed gas chamber to the mix and as an example the gas shock will extend all by itself to the top of the travel when uninstalled. All most all shocks available now are gas shocks. Someone out there who has the prerequisite engineering degree can explain why gas shocks are supposed to be superior. 

A video from my favorite program, "How it's Made"

 

Jeff Beyer temporarily retired from Trailer Transit
2000 Freightliner Argosy Cabover
2008 Work and Play 34FK
Homebase NW Indiana, no longer full time

Link to comment
Share on other sites

I could be wrong, it was a long time ago when I read a technical article in a motorcycle mag about the latest thing, Gas Shocks........  I believe the word "gas" is used because nitrogen is used in place of air within the shock body.  This is because nitrogen won't aerate the oil as it's forced through the metering orifices.  Foamy oil doesn't do much to dampen the motion.  Some "Gas Shocks" have a remote reservoir to help keep the oil and nitrogen separated.  Mostly seen on high performance applications.

KW T-680, POPEMOBILE
Newmar X-Aire, VATICAN
Lots of old motorcycles, Moto Guzzi Griso and Spyder F3 currently in the front row
Young enough to play in the dirt as a retired farmer.
contact me at rickeieio1@comcast.net

Link to comment
Share on other sites

On ‎4‎/‎15‎/‎2017 at 4:52 PM, beyerjf said:

A gas shock still has the conventional oil damping valving, typically 50-50, meaning the valving is set to be equal on extension and compression . Add a compressed gas chamber to the mix and as an example the gas shock will extend all by itself to the top of the travel when uninstalled. All most all shocks available now are gas shocks. Someone out there who has the prerequisite engineering degree can explain why gas shocks are supposed to be superior. 

A video from my favorite program, "How it's Made"

 

Hi Jeff,

Thank you for posting the video. Now I know how shocks are built. I had to idea how they where manufactured.

Al

2012 Volvo VNL 630 w/ I-Shift; D13 engine; " Veeger "
  Redwood, model 3401R ; 5th Wheel Trailer, " Dead Wood "
    2006 Smart Car " Killer Frog "
 

 

Link to comment
Share on other sites

13 hours ago, noteven said:

Don't be scared to check pricing on maintenance parts at your Kenworth or Peterbilt dealer - they sell an all makes line from Paccar Parts called TRP. 

The other thing is...if you have a Volvo and there is a Mack dealer near you, it is possible to get the identical Volvo part far cheaper. At least on most things that cross over.

Jack & Danielle Mayer #60376 Lifetime Member
Living on the road since 2000

PLEASE no PM's. Email me. jackdanmayer AT gmail
2016 DRV Houston 44' 5er (we still have it)
2022 New Horizons 43' 5er
2016 Itasca 27N 28' motorhome 
2019 Volvo 860, D13 455/1850, 236" wb, I-Shift, battery-based APU
No truck at the moment - we use one of our demo units
2016 smart Passion, piggyback on the truck
-------------------------------------------------------------------------
See our website for info on New Horizons 5th wheels, HDTs as tow vehicles, communications on the road, and use of solar power
www.jackdanmayer.com
Principal in RVH Lifestyles. RVH-Lifestyles.com

Link to comment
Share on other sites

19 hours ago, beyerjf said:

A gas shock still has the conventional oil damping valving, typically 50-50, meaning the valving is set to be equal on extension and compression . Add a compressed gas chamber to the mix and as an example the gas shock will extend all by itself to the top of the travel when uninstalled. All most all shocks available now are gas shocks. Someone out there who has the prerequisite engineering degree can explain why gas shocks are supposed to be superior. 

A video from my favorite program, "How it's Made"

 

The sole purpose of the gas, is to reduce foaming of the hydraulic fluid within the shock reservoir.  That is what makes them superior to non gas. 

John

Southern Nevada

2008 Volvo 780, D13, I-Shift

2017 Keystone Fuzion 420 Toyhauler 

2017 Can-Am Maverick X3-RS

 

ALAKAZARCACODEFLGAHIIDILINIAKSKYLAMAMNMS
event.png

 

Link to comment
Share on other sites

  • 5 months later...

Archived

This topic is now archived and is closed to further replies.

RVers Online University

mywaggle.com

campgroundviews.com

RV Destinations

Find out more or sign up for Escapees RV'ers Bootcamp.

Advertise your product or service here.

The Rvers- Now Streaming

RVTravel.com Logo



×
×
  • Create New...