Hey guys just wondering. I have a 620 4 speed l20b dropped 3 inches and I'm having issues with axel wrap any ideas on how to fix this issue or info??? I tried to search it but it only talks about raised 620s
7 replies to this topic
#2
datzenmike
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KING RAT
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Posted 17 April 2017 - 06:46 AM
Make sure your U bolts are on properly and tight.
New shocks will definitely help.
This is not a common problem for the 620, so did you remove a leaf? Put them back on, or add one..
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#3
DaBlist
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Datsun Mechanic
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Posted 17 April 2017 - 07:16 AM
Common problem when you have more torque /axle twisting than the leaf springs can handle. If you have lowering blocks they increase the torque leverage the rear axle has on the springs or removed leafs lessons the twisting the springs can handle. Many have added a link to handle the twisting so the springs mostly just support the load.
Some designs mount above the axle and some below. There are factory designs that use just one mounted close to the center of the axle also
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#5
Royal Sierra
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Posted 19 April 2017 - 11:19 AM
Check your center pins that go through the leaf pack. If you have lowering blocks sometimes the nipple on the top can shear off causing this. I've had this happen a couple times.
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#6
distributorguy
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Posted 19 April 2017 - 11:19 AM
I'm willing to bet what you're feeling has more to do with a driveline angle issue. Have you added a spacer at the carrier bearing to straighten driveline angles? It may be sitting lower than the pinion, but should be mid-way between the transmission output shaft height and the pinion flange height. Have you corrected the pinion angle after the drop? Did your new U-bolts come loose? I'd suggest double nutting or using nylock nuts.
Is it really axle wrap or a vibration when accelerating? If its just a vibration, you need to drop the pinion nose, likely with tapered shims at the leafs.
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#8
G-Duax
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prickly in San Antonio
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Posted 19 April 2017 - 11:46 AM
I snapped 2 leaf springs due to axle 'wrap', or as I called it, wind up.
If I had found some good leaf springs, it would have gotten bottom mount traction bars, or 'slapper bars' Waffle calls them.
But couldn't, so it got a 4-link set-up. Did a thread last week about it.
Beebani makes a 3-link + Watts set-up (5-link?) in kit form.
DaBlist, the set up in your second picture won't fit the 620, no room above the axle.
If I had found a pair of main leafs locally, I was going to use the stock bottom plates that the shocks mount to, and just weld some square tune to them to make the traction bars. The end runner bump stops are easy to find.
- Charlie69 likes this
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Don't be that person !
