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JB3 · 08-16-2013, 11:54 AM

so, swapped over to 4.56 from the 3.23

here are the two rear ends, 4.56 built into a 97 diff on the left-

also put in steel leaf springs with a higher load capacity. I did make the van heavier doing this, Id estimate each leaf was 3 times heavier than the fiberglass monoleaf. However, the fiberglass had to go, not so much the springs themselves as the hangars were close to failure

4.56 diff installed-

The immediate difference is no sluggishness in first, and I can pull overdrive on the highway now! very excited to see what new MPG numbers this might present for me.
I can also do hill starts, which was a hit or miss thing with the 3.23.

08-16-2013, 11:54 AM	#34 (permalink)
JB3 EcoModding Lurker Join Date: Dec 2012 Location: Rhode Island Posts: 34 Work Van - '89 Chevrolet Astro 90 day: 28.43 mpg (US) 240D - '83 mercedes 240D Thanks: 0 Thanked 9 Times in 5 Posts	so, swapped over to 4.56 from the 3.23 here are the two rear ends, 4.56 built into a 97 diff on the left- also put in steel leaf springs with a higher load capacity. I did make the van heavier doing this, Id estimate each leaf was 3 times heavier than the fiberglass monoleaf. However, the fiberglass had to go, not so much the springs themselves as the hangars were close to failure 4.56 diff installed- The immediate difference is no sluggishness in first, and I can pull overdrive on the highway now! very excited to see what new MPG numbers this might present for me. I can also do hill starts, which was a hit or miss thing with the 3.23.