Cracked Lowering Blocks

[fasttback]

Both of my 1" lowering blocks have cracked down the middle perpendicular to the leaf spring. I believe this is related to the arc of the spring and straightness of the lowering block - something had to give. Has anyone else had this problem? How did you correct it?

I thought about cutting the lowering blocks to match the curvature of the leaf spring?

 

[rpm182000]

what material are the lowering blocks made off? if there steel you could heat them to the desired shape.

 

[mrmustangman357]

are your blocks a piece of cast aluminum? Those like to crack if they are made from junk metal. The square tube ones (at least the ones I've seen and used) tend to flatten that part of the spring. It wouldn't be quite advisable to grind it to match the curvature of your spring. At jounce, the leaf springs arch changes and the new radius on your blocks can cause the rear end to tip front or back. If you look into the square tubing blocks, they are made of such a resilient steel that you won't encounter any cracking.

 

[fasttback]

Looks like cast aluminum (and thinner than most). Where do you purchase these square tube ones?

 

[mustangmike6996]

who makes the steel lowering blocks???

 

[10secgoal]

Go to an off road trucking place12sec67 used to break them like they were free until he found the steel ones.

 

[mikethebike]

I made some from billet bought from a scrape metal yard for $1 per pound! Call the local yards and ask wht they have that is close to the size you need. Even if yo have to go toa macine shop and have them cut, drilled and studed you will probably still spend only what you do to buy ready made pieces of junk.

 

[RMODEL65]

theres a reason lowering blocks arent considered safe. plus the extra lenght of the bolts require constant tightning because a longer bolts stretches easy

 

[mrmustangman357]

really there is a reason they are safe? lol

 

[mikethebike]

theres a reason lowering blocks are considered safe. plus the extra lenght of the bolts require constant tightning because a longer bolts stretches easy

Suspension u-bolts are grade-3 thread (I think it's grade 3..I may be wrong on the exact level of interferrence) which is self locking. Unless you thought they were defective and ran the threads with a dye. THEN they would loosen over time.
The ONLY disadvantage I see to blocks is the extra leverage it gives the axle as it tries to go backwards under acceleration.

 

[10secgoal]

Hmm, just saw scott drake sells billet pieces now also.

 

[RMODEL65]

Suspension u-bolts are grade-3 thread (I think it's grade 3..I may be wrong on the exact level of interferrence) which is self locking. Unless you thought they were defective and ran the threads with a dye. THEN they would loosen over time.
The ONLY disadvantage I see to blocks is the extra leverage it gives the axle as it tries to go backwards under acceleration.

it has nothing to do with the threads and the bolts becoming loose. it has to do with the length of the bolts ever seen a show where a guy bends a long meal rod with his bare hands?? well take that same rod and cut it in half and its alot harder to bend is it not??

 

[daddy oth]

fasttback,

did you ever replaced that craked lowering block.i bought 2 set awhile back one is belltech and the other one is from MP.i don't know which is which i know i have one pair of 1" block around here somewhere you can have it if i find it.

 

[fasttback]

fasttback,

did you ever replaced that craked lowering block.i bought 2 set awhile back one is belltech and the other one is from MP.i don't know which is which i know i have one pair of 1" block around here somewhere you can have it if i find it.

No I have not bought any yet, but I won't turn down some free ones. If you find them and you work in Lodi, I could meet you at the A&W Thursday evening...it's cruise night.

 

[daddy oth]

No I have not bought any yet, but I won't turn down some free ones. If you find them and you work in Lodi, I could meet you at the A&W Thursday evening...it's cruise night.

i will be at my brother's house this sunday to look for it.i think it in the trunk of my '66 coupe.i didn't know there was a cruise night in lodi but couldn't make it.if you ever see a yellow '98 cobra w/dd bullitt flag me down.the only place i know north of kettleman is AVENUE GRILLE my fav. place to eat.

i'll let you know by this weekend

 

[mikethebike]

it has nothing to do with the threads and the bolts becoming loose. it has to do with the length of the bolts ever seen a show where a guy bends a long meal rod with his bare hands?? well take that same rod and cut it in half and its alot harder to bend is it not??

You know, I understand perfectly well the principle of leverage. It has nothing to do with leverage, the bolts should be grade-8...I doubt seriously you will stretch them too far by driving the car anymore than you will the 3/8" bolts on a set of Crower 5.315" rods at 7500 rpm in a BOSS-302. That is not to say YOU wouldn't put a 48" breaker bar on the socket and attempt to torque them to 500 ftlbs. Besides, the last time I looked at a Mustang leaf spring rear suspension the springs were UNDER the axle so, the greratest loading being under compression, it would push the axle housing into the spring and not away from it. Thereby actually lessening the loading of the u-bolt.
Someone tell me...with proof...I'm wrong on this.