Bump steer and other questions - Page 2 - JeepForum.com
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Cherokee & Comanche Forums > XJ Cherokee Technical Forum > Bump steer and other questions

The Original 3/8" Ruffstuff Diff Cover!Ruffstuff Axle Simple Swap Kit!The Ruffstuff NOT Universal 4 Link Kit!

Unread 07-11-2012, 09:06 AM   #16
Agony Wagon
Agony Wagon's Avatar
1995 XJ Cherokee 
Join Date: Aug 2008
Location: , Ohio
Posts: 1,830
What does it take to get them the same length? What else do I have to buy???

Agony Wagon is offline   Reply With Quote Quick reply to this message
Unread 07-11-2012, 09:59 AM   #17
Registered User
1984 CJ7 
Join Date: May 2008
Location: Monument Colorado
Posts: 5,840
Don't worry about that. The effect of unequal length arms will be imperceptible from the picture you showed.
foggybottombob is offline   Reply With Quote Quick reply to this message
Unread 07-11-2012, 05:50 PM   #18
Registered User
2006 LJ Wrangler 
Join Date: May 2009
Location: 34*24'N, 119*42'W, SoCal
Posts: 3,892
Originally Posted by foggybottombob
I don't understand what any of this has to do with a plane as someone mentioned
Since everything else you said is nearly spot-on, I'll not muddy the waters, but will add this to clarify the "shared plane" concept. Notice in diagram 3 below the tb and dl are parallel, but not in the same plane (fore to aft) and not sharing a radial center, so their arcs of travel are not common and bumpsteer is inevitable. I hope it helps. Here's the link for the original thread: http://www.jeepforum.com/forum/f9/tr...tions-1356624/

Originally Posted by flying_bosun

At issue specifically was the "parallel" relationship required to avoid bump steer.

We've all heard that the TB and DL must be parallel and it's been suggested that with a DPA this could be accomplished by raising the axle end of the TB or by dropping the TB frame end. Initially this seemed reasonable to me from a geometric stand-point, but upon further examination it turns out not to be the case; the problem is that our axles articulate.

Here are some rough diagrams that may help some to understand what I mean.





For lack of a better explanation, bump steer occurs when the relative arcs' of travel don't share a (nearly) common center. This is because as the axle articulates, the push/pull forces acting on the axle via the track bar are at times contrary to the push/pull forces acting on the steering knuckle via the drag link.
[URL="http://www.grimmjeeper.com/gears.html"][COLOR="Red"][SIZE="3"]Gear-Calculator[/SIZE][/COLOR][/URL] [URL="http://www.stu-offroad.com/siteindex.asp"][COLOR="White"][SIZE="3"]Stu Can Help You[/SIZE][/COLOR][/URL] [URL="http://www.berrysprinter.com/jeepparts.php"][COLOR="Blue"][SIZE="3"]Part Names and Numbers[/SIZE][/COLOR][/URL] [URL="http://www.wholesalemopar.com/"][SIZE="3"][COLOR="Red"]Dealer Supplied Parts and ask for "Jeep Club" Prices[/COLOR][/SIZE][/URL]

[QUOTE=Ron Paul]“Liberty is lost through complacency and a subservient mindset. When we accept or even welcome automobile checkpoints, random searches, mandatory identification cards, and paramilitary police in our streets, we have lost a vital part of our American heritage. America was born of protest, revolution, and mistrust of government. Subservient societies neither maintain nor deserve freedom for long.”
― Ron Paul[/QUOTE]

[CENTER][SIZE="5"]"Did [I]you[/I] exchange your walk-on part in the war for a lead role in a cage?"[/SIZE][/CENTER]
flying_bosun is offline   Reply With Quote Quick reply to this message

bump steer , track bar

Quick Reply

Register Now

In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools

Suggested Threads

Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.