Grassroots Motorsports

Subscribe get a full year for only $23.95 Sample Free Test Drive—no strings attached

Login to post Forums » Grassroots Motorsports » Rear shocks breaking at welds.

• 

  Jan. 8, 2012 12:20 p.m. ThePhranc Reader

  Just got back from NC and its horrible roads with my 1980 AMC spirit.

  The thing has massive rear tires and sits on leaf springs. The shocks are Monroe Sensatracks. The car broke the pass side and the guy replaced it with a new one before I got there. On the test drive it broke the driver side and he just gave me cash back to cover cost. They bust where the lower bushing is welded on. All there is in the back is leaf springs keeping this straight. Would the lack of a centering lateral bar be putting too much stress on the shocks or are these shocks junk? If its junk shocks whats a good up grade? If its lack of bar what kind of maths are involved to get it right? Add two and triangulate? Links to good reading on the subject?

• 

  Jan. 8, 2012 12:30 p.m. Streetwiseguy SuperDork

  If the leaf springs are allowing the diff to move enough to strss the welds, there is something wrong with the bushings or shackles. Are they somehow mounted wrong, so the up and down movement is rocking the lower mount on the axis of the bolt instead of twisting the rubber? Did that sentence make any sense at all?
  

  Edit: Do they have a pin mount on the bottom? If so, have the rubbers been overtightened, causing the pin to bend?

  You've either got real bad shocks, or a bad binding situation, I'd say.

• 

  Jan. 8, 2012 12:47 p.m. ThePhranc Reader

  Its a ford 8.8 stuffed under an AMC spirit. The geometry may be off causing it to pivot on the wrong axis.

  The shocks are mounted on a plate that is affixed to the springs at the same place the springs mount to the rear with U bolts One infront of the rear and one behind.

• 

  Jan. 8, 2012 12:55 p.m. DILYSI Dave SuperDork

  Leafs don't need lateral locating - they do that on their own. Sort of. They did put a track bar with the front leafs on my YJ, and it is scarier without it. If the axle is moving a lot, I'd be looking at the leaf spring bushings.

• 

  Jan. 8, 2012 1:21 p.m. ThePhranc Reader

  I planned on poly bushings anyway so I'll start there I guess. All this week I'm going to take an hour or two each day to check over every bolt and screw.

• 

  Jan. 8, 2012 2:38 p.m. emodspitfire Reader

  Since it's a non-stock axle....Are the shocks too long or too short?

• 

  Jan. 8, 2012 3:08 p.m. ThePhranc Reader

  emodspitfire wrote:

  Since it's a non-stock axle....Are the shocks too long or too short?

  After going to the AMC forum it looks like they are the wrong shocks period. So first I'll buy the correct ones for the car originally and see how they do. At only $10 a piece I wont mind bust a few more. If it all fails I'll measure travel and find an appropriate shock.

• 

  Jan. 8, 2012 3:25 p.m. warpedredneck New Reader

  sounds like you are topping out the shocks, for all the time it takes measure them first

You'll need to log in to post.

• 
• 
• 
• 
• 
• 

• Jump to
• Top
• Grassroots Motorsports
• Off-Topic
• Sprockets
• $200X Classifieds
• Classic Motorsports