Rear Springs

[Nettlesd]

I had the 99 SHO inspected and it failed because the inspector said both rear springs were broken. Not much of a mechanic so I got a local mechanic to replace the rear springs. I just bought the rear springs from Rock Auto that said they fit the car.

Now, the rear end feels like it has air shocks that are fully extended going over any bumps or expansion joints. The rear end is super stiff.

What are my options? Did the mechanic not properly replace the springs? Maybe he has the rear shocks in a bind? Not even sure if that's possible. Could both rear shocks be bad and need to be replaced?

I don't want to just throw money at it. I want to know what might be the problem and get it fixed. If it needs new rear shocks then I'm fine with that as long as that's the problem.

What do you think?

 

[gamefanatic]

Which suspension kit did you purchase? There are a couple.

There are a couple of things that will change with any of the aftermarket versions.
1) Spring capacity. SHO's, even non-sho's have different capacity springs. If you got a quick strut, your mechanic replaced your original spring and thus your ride response will be changed.

2) The new strut works differently than OEM struts. They are passive, so they will be at near full height and will compress and rebound at a rate based on the design the manufacturer uses. OEM will rebound differently at low speed vs high speed. Aftermarket will likely target a more middle of the range. Since they are new they will take a bit to settle in. I'm not positive, but I think some of the rears are gas struts. Though that may only be on wagons.

I prefer the Monroe quick struts, but they too will be different than OEM.

 

[stephen newberg]

From the sounds of it, you just replaced the springs, correct? If it changed the feel hugely, it could be either the springs are not the right ones or if the old springs have been broken the entire time you owned the car, you have never felt it with proper springs. Both of these will cause huge changes to the feel of the rear of the car. First, check the part numbers for the springs that were put on to see if they are the right ones. If they are, then we can go further to see if the struts are also a problem or you or just not used to what the car was supposed to actually feel like.

pax, smn

 

[NoSlo]

Did you get the "broken springs" back? Skeptical..

If you got Moog, the ones listed are non-progressive rate 94. They instead should be relatively soft-riding vs original at 160 or so. Sharing the part number you purchased may allow us to evaluate your choice.

80093:
Bar diameter 0.515
Spring Rate 94
Load 543
Install Height 10
Free Height: 15.88

Even softer than the cargo coil option some use (and sometimes cut) for stiffness:

Moog rear cargo coils CC859 (progressive)
capacity : 455 lbs
spring rate : 137-349 (!) lbs/inch
wire diam. : 0.59 (0.60 measured)
1.57 cps
inner diam. : 5.22
free height : 14.50 (Ford stock is 15.88)
installation height : 11.25 (Ford stock is 10)

Struts and springs somewhat go together, the damping rate of the strut works together with the spring, so this was perhaps the time to have replaced the strut also. Bad rear struts give a harsh rebound feeling going over road bumps, it's not "stiff" but it's a strange uncontrolled feeling like the bump is 3x as bad and keeps on going. If the struts are good, the soft spring may be overdamped.

You can jump on your back bumper and see that it barely moves down and rebounds back to the original position without overshoot on a fresh set of struts and springs.

 

[GEN 3 SHO FAN]

**, it seems someone is recycling my old posts... Sadly, he didn't copy and paste the good part and don't give the link to my searches...

I spent many time (days) behind my computer comparing all the specs from each spring available on Rockauto.

Overall, we, Gen 3 SHO owners don't have many solutions... In fact, there is more solutions in lowering springs than stock height (3/4 vs 2).

You probably took the 80093 for the rear, did you ? If its the case, they are too smooth for the sport behavior of the SHO, even with a SARC struts (96 to 98). They will probably broke in some years. Don't go that way. Even stock SHO rear springs will broke, they are just too weak.

The Moog CC859 are designed for taxi taurus. They are a lot stronger. Don't go that way if you feel the front is also sassy. You will have a real strong rear end with a bumping front, not very cool (but better than sassy all four wheels). If you have always some load in trunk, they will be great but with an empty trunk they are very stiff. I felt oversteer once on a curvy dry road and was a little bit surprised... The problem with CC859 is that you will have difficulty to find a stiff spring like them for the front. I know them, I'm running them presently.

Moog / TRW CC859 (very cheap, check for a 95 SHO to find them, same fitting for the rear)
https://www.rockauto.com/en/catalog...l+v6+dohc,1138957,suspension,coil+spring,7512

I give the link on my searches that led me to another solution (after many many comparisons) that I haven't still tried until today. I was in the hope to try them this summer but time is lacking from now. This link will also give you a front solution replacement not mentionned in Rockauto for your year.

https://shoforum.com/index.php?thre...859-review-and-possibles-other-matchs.133054/

The other solution could be the Moog CC240. They are progressive and were made for the front of Camry. The only prob I saw with them is their diameter, they are 3/16 inch larger than our rear ones, all the rest fit according to the comparisons I made (see link). I will not repeat all I wrote elsewhere but they are a bit weaker than CC859 but are also progressive, seems a good replacement but no one tried them since I spoke of them in 2017. I assume their stiffness will fit with the stock front ones.

https://www.rockauto.com/en/partsearch/?partnum=cc240

Rockauto for our springs isn't 100% reliable. Many mechanics made mistake between Taurus and SHO parts too... Hope you kept your old strut.

If you have questions, let me know.

 

[stephen newberg]

I second the solution of going with lowering springs, having done so many years ago now. But I am no longer sure what is still available in this route. I do not think the Eibachs I am using are still on the market.

pax, smn

 

[GEN 3 SHO FAN]

Lowering solution force you to play with camber and alignment...

For stock height, we can run Moog/TRW 80108 on front end and CC859 on rear end. They can be a real good maintenance upgrade (really cheap if you bought the TRW version) and can be also considered as a smooth performance upgrade (the overall car stiffness is higher by around 20%, +10-15% on front and +40% on rear).

The good point with this settup is you don't have to play with swaybars anymore to keep the car flat. No more SAS and bodyroll will be 5-10% of the stock feeling.

The downside is your front end will bouncing a little bit more than the rear end. (Better with some weight in the trunk.)

 

[stephen newberg]

Yes, they do. You have to punch out the spot welds at the tops of the strut towers and install adjusting plates. Its not hard, and you can actually end up saving the costs easily in lowered tire wear. The weld fixed situation from the factory is a really bad idea from the start anyway.

pax, smn

 

[Nettlesd]

Sorry Everyone. I wasn't getting any responses when someone replied.

Here's what I ordered. Only the springs were replaced. I did not replace the struts in the rear.

1999 FORD TAURUS 3.4L V8
MOOG 80093 Coil Spring $ 39.79 $ 0.00 1 $ 39.79

I will admit, I don't drive this car. It's my daughter's car so when I picked it up and drove it, I felt the rear was way too strong going over a bump.

If anyone is interested. She's ready for an upgrade so if anyone would like a very nice car.

 

[stephen newberg]

If you are goign to advertise the car for sale, and you have now posted in 2 places about wanting to sell it, I would appreciate if you took that to the sales section and paid Bizzy the fee to do so. I will check back in a day or two, and if you have not, I will be editing out your ad copy.

pax, smn

 

[Nettlesd]

Sorry, didn't realize you had to pay to advertise. I'll edit my posts.

 

[Nettlesd]

I don't see how to edit my post so I'll let you do it.

 

[stephen newberg]

No problem, I will take care of it. Go ahead and list the car in the sales section. I think a fair number of vehicles turn over there.

pax, smn