Suspensión question

[Amp653]

But did they install the replacement specifically for the PPV suspension? The PPVs are spec'ed to have firmer shock and strut valving. As @swathdiver said, change the tires if it still has the ones spec'ed for the PPV, even if it's just the size (not necessarily the speed rating). If this doesn't suffice, get "civillian" springs and shocks/struts. The springs can be found everywhere new or from people that lowered or lifted their rigs. The tires and swapping out the springs will raise it to standard Tahoe height. The taller tires will make your speedometer read slow, too.




Bilsteins are often hailed as the best-riding shock on these, but there are others that are a little more budget-friendly. I think the Monroe Sensa-Trac line is one example of these. No personal experience, though.

The struts were PPV specific as the guy I bought it from spoke to tech who did work before it went to auction. I see a lot of springs that are “drop springs”. Not supposed to make that much difference. I would think it would give me same ride as I have now. It seems it has that bounce/rough ride that the old crown vics used to have

 

[iamdub]

The struts were PPV specific as the guy I bought it from spoke to tech who did work before it went to auction. I see a lot of springs that are “drop springs”. Not supposed to make that much difference. I would think it would give me same ride as I have now. It seems it has that bounce/rough ride that the old crown vics used to have

Ah, so the parts replaced were while still in service. Not all drop springs ride firmer. If you don't want it higher, then you'll have to replace the PPV parts with lowering counterparts for a standard Tahoe.

If it were mine and I wanted to make it ride softer but also keep it about the height it is now: Taller tires to equal ~32" diameter, spring and strut assemblies from a standard/civilian Tahoe (bonus points if you score those for a ZW7-equipped truck), drop spindles or mount the struts to the underside of the control arms (use ONLY the special bolts for this), 3" drop coils for the rear, quality shocks and shock extenders if you don't find good shocks that are shorter.

As cheap as they are, you might wanna replace all the sway bar and end link bushings. Shorten the end links as necessary for the drop, unless the PPV ones are already shorter.

 

[Amp653]

Ah, so the parts replaced were while still in service. Not all drop springs ride firmer. If you don't want it higher, then you'll have to replace the PPV parts with lowering counterparts for a standard Tahoe.

If it were mine and I wanted to make it ride softer but also keep it about the height it is now: Taller tires to equal ~32" diameter, spring and strut assemblies from a standard/civilian Tahoe (bonus points if you score those for a ZW7-equipped truck), drop spindles or mount the struts to the underside of the control arms (use ONLY the special bolts for this), 3" drop coils for the rear, quality shocks and shock extenders if you don't find good shocks that are shorter.

As cheap as they are, you might wanna replace all the sway bar and end link bushings. Shorten the end links as necessary for the drop, unless the PPV ones are already shorter.

Thanks very much for this info. I found a 2” drop spring set so far for rear. Do I need extenders to add in a set of billsteins or Monroe’s for example?

 

[iamdub]

Thanks very much for this info. I found a 2” drop spring set so far for rear. Do I need extenders to add in a set of billsteins or Monroe’s for example?

If you get shocks for a stock, standard Tahoe, then yes, you need extenders. Actually, I'd go this route versus trying to find a quality shock that was also about 2" shorter (a "drop shock"). It's easier to keep as much stock as possible so future replacement parts will be easier to find.

2" extenders on a 2" drop means the rear will have it's normal range of motion- "stock travel".

What's the brand of the 2" drop springs? Have a part number or link?

 

[Amp653]

If you get shocks for a stock, standard Tahoe, then yes, you need extenders. Actually, I'd go this route versus trying to find a quality shock that was also about 2" shorter (a "drop shock"). It's easier to keep as much stock as possible so future replacement parts will be easier to find.

2" extenders on a 2" drop means the rear will have it's normal range of motion- "stock travel".

What's the brand of the 2" drop springs? Have a part number or link?

Sorry, im having a hard time wrapping my head around it. You’re explanations are great though. I’m looking at Mcguaghys 2” rear drop for chevy tahoe 2015-2019.

 

[iamdub]

Sorry, im having a hard time wrapping my head around it. You’re explanations are great though. I’m looking at Mcguaghys 2” rear drop for chevy tahoe 2015-2019.

McG has good stuff.

What're you not understanding? Maybe I can explain another way.

 

[Amp653]

McG has good stuff.

What're you not understanding? Maybe I can explain another way.

If I buy the 2” drop springs, then I would have to buy a set of good “standard suspension” shocks with a set of extenders to replace what I currently have? Which is this:

 

[iamdub]

If I buy the 2” drop springs, then I would have to buy a set of good “standard suspension” shocks with a set of extenders to replace what I currently have? Which is this:

Correct. Whatever you drop a vehicle via shorter springs, the shocks are compressed that same amount.

A 2" drop spring will lower the frame 2" closer to the axle and the shocks will be compressed 2". It's just like hitching up a heavy trailer that squashes it all down 2". The shocks will then be 2" closer to bottoming out. They have lost 2" of their travel.

You can get shocks that have a 2" shorter body ("drop shocks") so that the shocks will have their full amount of travel. Or, you can keep stock-length shocks and get 2" extenders. These put the lower mounting point of the shock the same distance from the upper mounting point that it was before the drop. With the mounting points the same distance apart, it's as if the vehicle was never lowered so a stock shock will fit and operate as normal.

Of course, this is all relating to the rear. There are no extenders for the front to make up for a lowering spring since the spring rides on the "shock". To lower the front without losing any suspension travel, you'd use spindles or mount the strut to the underside of the control arm. Spindles have the least affect on the geometry elsewhere and will require minimal adjustment for the alignment. Relocating the strut mount under the control arm is super cheap (about $30 for the bolt kit). It also poses relatively minimal change to the geometry as it simply drops while remaining within the suspension's normal range of motion. Unlike using spindles, the control arms are cycled upwards a few degrees, so the ball joints and all are now resting at that position. For such a minimal and routine drop, I'd have to go with spindles. On that note, while the McGaughy spindles maintain the factory suspension's positions and geometries better than Belltech and the other brands, they "only" drop 1.75". The way they designed the spindle to maintain those geometries limited the drop to 1.75". If you want the full 2", you'll have to accept altered control arm and ball joint angles inherent to the other brands. I don't intend for this to sound like I'm bashing Belltech, DJM, or whoever else other than McG that makes spindles for these things. Just listing the facts so you can choose based on what's important to you. Actually, to balance the scales here, the McG spindles use a stud for the top center bolt of the hub assembly. You must follow the installation specs to the letter- no half-assing/"just make it really tight" is gonna fly. Too much or not enough torque and/or improper torqueing sequence can cause this stud to shear. I've broken one on each side while driving (on two separate occasions). When replacing the broken studs, I adhered strictly to their instructions and haven't had any problems since. I haven't driven it any easier, either.

 

[swathdiver]

I just remembered that the XFEs were lowered. Depends on how low you want to go. They are low like the PPV and SSV but with regular height tires.

 

[Amp653]

Correct. Whatever you drop a vehicle via shorter springs, the shocks are compressed that same amount.

A 2" drop spring will lower the frame 2" closer to the axle and the shocks will be compressed 2". It's just like hitching up a heavy trailer that squashes it all down 2". The shocks will then be 2" closer to bottoming out. They have lost 2" of their travel.

You can get shocks that have a 2" shorter body ("drop shocks") so that the shocks will have their full amount of travel. Or, you can keep stock-length shocks and get 2" extenders. These put the lower mounting point of the shock the same distance from the upper mounting point that it was before the drop. With the mounting points the same distance apart, it's as if the vehicle was never lowered so a stock shock will fit and operate as normal.

Of course, this is all relating to the rear. There are no extenders for the front to make up for a lowering spring since the spring rides on the "shock". To lower the front without losing any suspension travel, you'd use spindles or mount the strut to the underside of the control arm. Spindles have the least affect on the geometry elsewhere and will require minimal adjustment for the alignment. Relocating the strut mount under the control arm is super cheap (about $30 for the bolt kit). It also poses relatively minimal change to the geometry as it simply drops while remaining within the suspension's normal range of motion. Unlike using spindles, the control arms are cycled upwards a few degrees, so the ball joints and all are now resting at that position. For such a minimal and routine drop, I'd have to go with spindles. On that note, while the McGaughy spindles maintain the factory suspension's positions and geometries better than Belltech and the other brands, they "only" drop 1.75". The way they designed the spindle to maintain those geometries limited the drop to 1.75". If you want the full 2", you'll have to accept altered control arm and ball joint angles inherent to the other brands. I don't intend for this to sound like I'm bashing Belltech, DJM, or whoever else other than McG that makes spindles for these things. Just listing the facts so you can choose based on what's important to you. Actually, to balance the scales here, the McG spindles use a stud for the top center bolt of the hub assembly. You must follow the installation specs to the letter- no half-assing/"just make it really tight" is gonna fly. Too much or not enough torque and/or improper torqueing sequence can cause this stud to shear. I've broken one on each side while driving (on two separate occasions). When replacing the broken studs, I adhered strictly to their instructions and haven't had any problems since. I haven't driven it any easier, either.

Very in depth and educational. Much appreciated. If I can get my hands on a set of factory springs from a regular LS or LT and use factory height shocks but just aftermarket then I would be in good shape. I’m trying to improve ride best I can. Just trying to be smart before throwing parts at it for a trial and error and hurting my wallet