Lowered questions

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Red85

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Greetings all ..

Bought my '85 C10 stepside lowered and trying to figure out by how much and how it was done!

I see people frequently measure ride-height at the wheel well so I did the same and get 28 inches (except my driver side front which for some reason is 29 inches)

A lot of things appear to have been done on the cheap so my first guess is that the original front coils were cut but I have not had them out to measure (yet).

I can't see how the rear was lowered at all - it all looks stock to me. But one thing that stands out is the u-bolts are pointing noticeably to the rear which suggests the axle is rotated (pinion up). I don't see any shim installed under the springs. Vibrates like hell though at 45 MPH and up so something needs sorting there. Got to measure some angles with the Tremec app on the phone.

But I think perhaps need to start with that front height difference as that might also be contributing to geometry issues!

Let me know what you think and if possible what stock ride-height might be.

Thanks as usual for reading ..

Rob
 

Scott91370

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The best and most accurate way is to measure from the center of the hub to the lip of the fender. This will account for actual lowering distance. If you measure from the ground to the fender lip you'll also include the distance the tire dropped the truck.

I don't have the measurement of stock distance so that's as far as I can help.
 

Lugnut

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The best and most accurate way is to measure from the center of the hub to the lip of the fender. This will account for actual lowering distance. If you measure from the ground to the fender lip you'll also include the distance the tire dropped the truck.

I don't have the measurement of stock distance so that's as far as I can help.


I have 2 stock ride height C10's in the shop one of them measures from center of front hub to fender lip 18.5" drivers and 19" pass., can't measure the rear bed is off. The other one measures 20" all the way around, but remember these are 40 year old springs.

That being said most of these truck very rarely sit level, especially with a full tank of gas on one side or another.

Also the stock ride height measurement will vary some with how it is equipped (AC / non AC, Big Block vs six cyl. and so on).

I hope this helps.


Is the rear axle on top of the rear springs or on the bottom of the springs? Got any pics they always help.
 

Red85

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The rear axle is below the springs, which is the stock arrangement I believe?
 

Catbox

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Photos are needed of this rear end set up.
That sounds like it is loose as the U bolts should be straight up and down.
 

Red85

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I'll try to get some pics
 

Scott91370

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I have 2 stock ride height C10's in the shop one of them measures from center of front hub to fender lip 18.5" drivers and 19" pass., can't measure the rear bed is off. The other one measures 20" all the way around, but remember these are 40 year old springs.

That being said most of these truck very rarely sit level, especially with a full tank of gas on one side or another.

Also the stock ride height measurement will vary some with how it is equipped (AC / non AC, Big Block vs six cyl. and so on).

Agree totally with all of this. But for finding out if it is lowered or not going with your average of around 19" from hub to fender lip would be close enough - at least for me.
 
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Scott91370

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edited to remove incorrect info.
 
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Red85

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Ok so measured from axle center to fender lip (wheel well) and was 16 inches on all corners except that driver side front at 17. It's funny I could have sworn the u-bolts were pointing back but when I checked today they are actually pointing forward. Took some pics and will attempt to post shortly. What's also interesting is that I had the axle up on jacks (and then also the rear frame on jacks after) to check spring action and whether or not I had posi and then had the truck out for a run and got up to almost 60 mph (afraid to go higher still lol) without feeling the nasty 'bucking' vibration I had earlier seen at 45 to 50 mph every time out. Could what I did have changed anything? Waiting for rain to quit so I can drive it again and see if anything really changed.
 

Zoomalot

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Pinion "UP"
Do you mean axle housing flipped upside down?
I think you have issues!!
 

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