Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - Strut rod???
Thread: Strut rod???
View Single Post
  #5 (permalink)  
Old 03-17-2003, 07:24 AM's Avatar is offline Moderator
Last wiki edit: How to rebuild a Rochester Quadrajet 4MV carbureto...
Last journal entry: How to change auto shift timing on 200R4
Last photo:
Join Date: May 2002
Location: Bakersfield
Posts: 8,450
Wiki Edits: 21

Thanks: 6
Thanked 45 Times in 33 Posts

The strut rod that Ford designed absorbs a very high percentage of the loading on the suspension system. Look at their robust design for the rod and its support and you get an idea of it's importance. All of the failures of the aftermarket MII suspension systems I have seem over the years are the result of poorly thought out modifications to this part. FOr example, simply welding a strut rod support to the frame with a couple of gussets will eventually result in either total over stress and breaking off the frame or surely fatigue fracturing over time. One of my 'favorite' passtimes is to go around rod runs and pointing out fratured welds on these installations.

Designs that eliminate the strut rods altogether should be investigated in detail before trusting them in a daily driver. They do fine in trailerd show cars or Friday night Sonic Drive In cars but in daily service they MAY be very dangerous. There have been pictures on this bulletin board of two separate failures of a popular after market x-member with strut rod eliminators. Although the x-member looked very robust, there is a design flaw that guarantees a fatigue crack failure. One manufacturer answered the failure by saying the "he tested his designs for two full weeks over rail road tracks and pot holes with no failures". This shows woefull ignorance of fatigue failure which is the biggest danger in a daily driver. Not only must a part be able to sustain large single loads which that guy's 'test' did fine, it must also survive much lower but repeated loads for a long time which is fatigue. Fatigue design investigates the effect of vibrations for millions of cycles and tens of years, not a two week drive around.

For my installations, I will use nothing but stock MII x-members and stock, bolt on with secondary x-member strut rod supports and all the rubber donuts that Ford used. They can be made to look very good - not like an Indy car, admittedly - but good enough to win awards. And most important, I know they are safe.
Reply With Quote