News

308 Rear Suspension Rebuild with Pics

Discussion in 'Technical Q&A' started by Birdman, Mar 8, 2004.

  1. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    A.K.A. How to spend a lot of money on stuff that nobody will ever notice except you…

    Hi Fchatters, I spent the winter rebuilding my 308's rear suspension. Not because I am a glutton for punishment or like to empty my wallet, but because this is one of those projects that is classified as a WYAIMAW project ("While You're At It, Might As Well…").

    It all started when I bought the car last spring and noticed that it made a lot of clunking noises from the rear suspension. The noises got quieter as the car warmed up and was driven, only to return when it was cold. The experts here at Fchat pointed me in the direction of the shocks. Apparently when they are old, they make a lot of noise. So, I decided to replace or rebuild the shocks. "Well," I thought, "While I'm at it, I might as well replace the suspension bushings." Fine enough. Next, Verell (Famous Fchat guru, who luckily for me, unluckily for him, lives about 45 minutes from my house) suggested that if you have to take the A arms out to replace the bushings, you might as well powder coat them. Heck, makes a good time to replace the fuel lines when the wheels and wheelwells are out. You have to remove the airbox to get to the carbs for the fuel line, so why not refinish the airbox too. You see where I'm going with this!! (There were suggestions of also rebuilding the brakes, etc. while it was all apart, but with a baby in the house, I thought I better keep it within the realm of reason.)
    So here it is. I rarely get the chance to "give back" to the Fchat community that has given so much knowledge to me, so I hope this helps someone out with their rear suspension rebuild.

    DISCLAIMER! I am not an expert mechanic or anything, sort of a learn as you go kinda guy, so if I did something really stupid, please be kind!


    Step 1
    Jack up the back of the car on both sides to get the rear wheels off the ground. Remove the back wheels.
     
  2. To remove this ad click here.

  3. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 2
    Remove the inner fenderwells (the fiberglass things that keep dirt from the wheels out of the engine compartment.) It's 6 obvious screws, then you have to twist it a little to get it to pop out. They are quite flexible and easy to remove.

    Step 3
    Unbolt the rear sway bar from both sides. As much as I tried to weasle out of doing this step, it was necessary, so save yourself the aggravation and just do it first! (For those of you looking to replace those sway arm bushings, I did a write up on that procedure in the old Fchat. It's in the archives.)
     
  4. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 4
    Unbolt the inner and outer nuts on the upper and lower A arms, as well as the top and bottom of the shocks. This is pretty straighforward unless the car was driven in the winter a lot and has stuck bolts. Fortunately, all the nuts are nylock type, which tends to seal the threads of the nut from the environment a bit. Mine were pretty easy to get apart. ALL the nuts and bolts are 19mm, so you need two decent 19 mm boxend wrenches and a 19 mm socket is helpful for a couple of them. One tip Verell gave me is to squirt some PB Blaster or similar penetrating goop onto the nuts the night before you start. It will soak in and help break the nuts free the next day. (Man, I hate it when I break my nuts free….)
     
  5. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 5
    As you disassemble the bolts on the outer A arms, keep very careful track of the order all the bushing parts come out, because there are a lot of them. The washers have a teflon coated side and a non-coated side. It's very important to reassemble correctly, so that the teflon side slides against the metal spacer and does its job. So be very attentive here. These components for the outer bushings don't seem to wear out that easily, and usually you can clean them up and reinstall. (This is what I did…mine looked fine) Good thing, since I hear replacement cost for these is astronomical and there is no cheap generic alternative.

    The bolts for the inner A arm connection are simple. I pulled them out, kept track of which way they were installed, then re-installed them in the chassis after the A arms came out so I would remember which way they went when it was time to put it back together. Good thing because it turns out that it took me 2 months to get everything ready to go back in! (I'm slow. Remember the baby?)

    Step 6
    The easiest way to remove the shocks and the upper A arms is to sort of remove them at the same time. The upper A arm can be removed from around the shock, but it's difficult. Same goes for the shock alone. Pulling them together is easier. Either that or pull the bottom A arm first and that buys you space to tak the upper A arm out from around the shock.
    Once the A arms are out, be careful to support the driveshaft and the remains of the hub. I hear that you can damage the bearings if you let it all just sit there too long.
     
  6. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Here's what the A arms look like when removed from one side. The smaller one is the upper.
     
  7. To remove this ad click here.

  8. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 7
    Okay so now the question is, what to do about the shocks? You have two options. You can send the shocks out to be rebuilt or just replace them. Truechoice (www.truechoice.com) or Koni will rebuild them. New shocks are about $150 from Tire rack. (www.tirerack.com). If you buy new ones, you still have to remove the shock from the spring somehow, which means either getting some spring compressors and doing it yourself, or taking the shocks to a shock place locally and having them do it. I decided to try just sending the shock/springs to Truechoice and have them do the work. It was easiest for me in terms of running around. Just box them up and ship. However, I had an unfortunate experience with Truechoice. (There is another thread on this.) In a nutshell, they charged me a hell of a lot more than they quoted. May advice? Just buy new shocks.

    You should definitely replace the shock bushings at this point. Even if they look okay, the rubber will be old and crappy. It's such a pain to get this far, might as well do it right. In my search for polyurethane A arm bushings, I looked hard to find poly shock bushings to save some money. I couldn't find anything! So I had to buy Ferrari ones at $20 a pop from Dennis McCann (www.allferrariparts.com). He had the best price in the U.S. Ferrari U.K. had a better price, but with shipping it was no better for me. If you are able to tack those parts into another order from Ferrari UK to amortize the shipping costs, it is cheaper to get them from Ferrari U.K. So anyway, you need 4 to do the rear shocks, so chalk up $80 plus shipping.
     
  9. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 8
    The A arms are painted steel and they have some little seams where road dirt and little sand grains get stuck. I started by cleaning the arms thoroughly in degreaser (citrus stuff).

    Step 9
    Here you can see that the old rubber-based bushings (the inner ones) are tack-welded into the A arms. This keeps them from possibly grinding against the A arm and wearing the mounting hole too big. To get these out, you have to grind off the welds with a little grinder. I used an inexpensive air grinder with a small stone that would fit in the space to grind them. Sparks flying, yee haw, what the hell am I doing to my expensive Italian car????

    Later ir turned out that I needed to get in a little tighter and Verell used his super tiny cutting wheel on it.
     
  10. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 10
    I decided to leave the bushings in place for the next steps, thinking that the bushings would protect the inner mounting surfaces of the A arm during the powder coat. However, it's the point of no return once you powdercoat the arms with the bushings installed because the heat will melt the rubber a bit.

    Step 11
    Now it's off to Verell's house to do some sandblasting and powdercoating. Verell's sandblast cabinet is just large enough to fit the arm inside, so it took a while to sandblast each piece. This took a long time. The pieces are strangely shaped and time consuming to sandblast. They come out nice and clean though!
     
  11. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    That blue stuff in the picture above is putty to keep the sandblasting from harming the smooth inner surface of the out A arm bushing mounting hole.

    Step 12
    Verell has a nice little setup for powdercoating. I always thought powdercoating was complicated, but it's pretty simple. Basically the way it works is you have a colored powder that you spray onto the piece. The powder has the consistency of baby powder, and it's available in lots of colors. Once sprayed onto the piece, you bake it in an oven at about 450 degrees F. The powder melts, becomes a nice even coating, then it cools to a hard-baked finish. To get the powder to mostly stick to the piece and not just fly all over the garage, the sprayer has an electrode in it. You connect a ground clip to the piece to be coated, and a couple thousand volts difference in potential from the sprayer to the piece makes the powder attracted to the piece and it sticks a little better. You need to regulate the pressure in the sprayer down to about 10-15 psi, or the stuff will go everywhere at the speed of sound!

    We fabricated some little hooks from coat hanger to hold the piece hanging from an oven rack to bake it. Then we sprayed and baked. Also, you need to mask off areas that you don't want to be sprayed (the outer bushing holes and the sway bar mounts) for which we used some aluminum foil and heat-proof fiberglass tape. The masking part is a tremendous pain in the butt.

    Verell has his wife's old kitchen oven converted for powdercoating duty. He removed the top burners so he can pile stuff on it in the garage without lighting anything on fire. Cheap and effective. Next time your wife starts talking about needing a new oven, just smile and say "Sure honey! Great idea!" Then you too can have the most expensive part of a powdercoating setup in your garage! If you don't want to start your own powdercoating factory, you can send these things out to be powdercoated too.
     
  12. To remove this ad click here.

  13. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 13
    Woo hoo! Check it out! After it's baked and cooled, it looks awesome! Too bad it takes hours and hours of work to sandblast and powdercoat all the parts. What a pain, but such a nice result!
    I would be lying if I told you that they all came out perfect. We are still on the learning curve. We over powdered one arm and it ended up goopy, and we undercoated the next and had to do it again. Oh well. This one looks good though!
     
  14. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 14
    Okay, so AT LAST it was time to press out the old bushings and put in new ones. We popped the first A arm into Verell's 3 ton press and…..jumped up and down on the lever. Nothing. A 3 ton press couldn't BUDGE the bushing even a mm. We checked to be sure that the welds were ground off enough. Yep. Now what to do?

    It's good to have friends. Even better to have friends that have friends. We visited a friend of Verell's. He has a 50 ton hydraulic press. That did the trick. Someone a while back posted something to the effect that you can whack the old bushings out with a hammer. Not mine. I forgot my camera that day, unfortunately, so I have no pictures. The 50 ton press looks like a hydraulic jack mounted on a be metal bench. We used up to 6 tons of force to remove the bushings.
    Here's a shot of the arm once the bushing was pressed out.
     
  15. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 17.
    Back at Verell's house, we pressed in the new bushings on his small press. With a little lube, they went right in there, as you can see from Verell's expression. (It's good to be the photographer sometimes!) The new bushings are from Energy Suspension, part number 13-3101G. To my knowledge these are the same part number and size for all 308 models, front and rear inner A arm bushings. I got mine at Suspension Restoration (http://www.suspension.com/ferrari.htm) and they cost $15.00 each. You will need 8 for the rear suspension (2 on each A arm). Chalk up another $120.00 plus shipping. They had them in stock and I got them in a couple of days. Very nice people to deal with.

    There is debate on the subject of aftermarket polyurethane versus stock Ferrari rubber bushings. The poly ones last longer and cost a lot less, but they give a harder ride. Some think the ride is better, some think the ride isn't really that different. The ride is much more a function of the condition/settings of the shocks than the bushings, and the change in bushing is pretty subtle to me. Then again I'm just a normal guy, not a race car driver.
     
  16. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 18
    Next we tack welded the bushings. "But do I have to weld the new bushings?"

    Everyone asks this. Short answer: Yes! If you don't, you can really screw up your A arms because the metal of the bushing can wear against the A arm. If you don't have access to a welder and someone that knows how to weld, take them down to a local welding shop. I doubt the guy would charge more than $20 to zap these in place. Takes just a few minutes.

    WARNING: shoot pictures of the welding process through a tinted welding mask! This could damage your camera! (Cool shot, eh?)

    Note Verell's nice clean welds.
     
  17. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Step 19
    Before final assembly, I hit the new bushings and the welds with a coat of POR 15 rust inhibiting paint.
     
  18. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Well from here it's pretty simple. Just reassemble everything in the reverse order that you disassembled it. It took me about 3 hours to put everything back together this morning. (The second side goes faster than the first!)

    There is debate as to whether the bolts should all be torqued with the suspension hanging (because the car is jacked) or if the car should bet sitting on the suspension at normal ride height when you tighten. Unfortunately, unless you have a 4 post lift and you can stand under the car while it's sitting on it's wheels, you really can't torque the suspension while loaded. So I just torqued mine down while it was jacked up and then put the wheels back on and lowered it. It seemed a bit high, so I jumped up on the bumper and the car settled back to it's normal height. Then I jumped up and down a couple times to the satisfying sound of a Ferrari with nice new suspension!

    Step 20
    The results? Well, it cost me a bit over $700 to do this job, including shocks and bushings. With new shocks, ironically, the price would have been probably $100 less. Most of the work I did is only apparent to me (I mean honestly, how many people are going to notice that the A arms are powder coated?) but it's nice to know it was done right. I expect that I will never need to replace the bushings again, since the poly bushings should easily last another 20 years. How does it drive? I have no idea. It snowed today!!

    I can't thank Verell enough for his help with this project. I spent quite a few nights over at his house getting help with various parts of the project, as well as learning from the master!
     
  19. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    I almost forgot...here are some shots of the bushing and the box for anyone interested in using these.
     
  20. pma1010

    pma1010 F1 Rookie

    Jul 21, 2002
    2,559
    Chicago
    Full Name:
    Philip
    Jonathan
    I did mine last winter. Good write up & pics. Nice to see the clean motor in the latter shots too! As you know, you'll need an alignment now.
    Philip
     
  21. AWulff

    AWulff Rookie

    Excellent step by step procedures. I am going to keep these in my 308 shop manual. Thanks again…
     
  22. Verell

    Verell F1 Veteran
    Consultant Owner

    May 5, 2001
    7,002
    Groton, MA
    Full Name:
    Verell Boaen
    Jonathan,
    Nice photos & writeup! Tnx for the credits for what little I did.

    Why don't you plan to bring your car over once the roads are clear. We can retorque the bushings under load.

    Just put it up on the lift, pull the rear wheels, loosten the bushing bolts, then load up the rear suspension by lowering it until the brake rotors sit on top of pair of ramps I have. When the car barely lifts off of the rear lift pads pads the rear suspension will be properly loaded. Then just torque the bolts, reinstall the wheel liners & wheels. Probably take 30-40 min.

    Then it'll be time to take it in for that rear suspension alignment.
     
  23. PSk

    PSk F1 World Champ

    Nov 20, 2002
    17,673
    Tauranga, NZ
    Full Name:
    Pete
    Very interesting.

    Hmmm, many cars have bushes just like that that press into either A arms or simply trailing arms and they NEVER move and do not need welding. Why are Ferraris any different?

    Reading how much force it took to push them out and new ones back in, they are NOT going to ever move, under suspension movement.

    Then again welding them does not hurt I guess and if that is what Ferrari originally did then I would do the same ... but I have done many NON-Ferrari bushes that are very similar concept and never welded any, and never had a failure ...

    Pete
     
  24. carl888

    carl888 F1 Rookie
    Silver Subscribed Owner

    Oct 31, 2003
    4,637
    Melbourne, Australia
    Full Name:
    Carl Jones
    Great post Jonathan, thnaks for all the pics. The expression on Verell's face using the press was wonderful! Just curious as to why you didn't do the bushes on the hubs though?

    Regards,

    Carl.
     
  25. enjoythemusic

    enjoythemusic F1 World Champ

    Apr 20, 2002
    10,675
    Worldwide
    Full Name:
    Steven
    Jonathan,

    CONGRATS and great pics/writeup! Now i know what to have done to the beast here during the next round of servicing (plus touch-up/respray front spoiler). Looking forward to seeing your GTB happily prancing the streets :)

    Enjoy the Drive,

    Steven R. Rochlin
     
  26. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    Thanks guys. Yeah, all fixed up just in time for the snow we had yesterday! D'oh!!

    Carll888- the outer bushes are metal collars and metal washers with teflon on them. They don't wear out very easily. I cleaned mine up and they looked fine, so there was no reason to replace them, especially considering what they cost.

    Birdman
     
  27. Birdman

    Birdman F1 Veteran

    Jun 20, 2003
    6,687
    North shore, MA
    Full Name:
    THE Birdman
    PSk-
    We asked this same question while we were pressing in the new bushings. ("Do we REALLY need to weld these things?") In all honesty, probably not. I seriously doubt they are going anywhere, given how tightly they are pressed in, but who knows how much force is on them under load (i.e. me driving!) so we figured they should be welded as the car came from the factory. There must be a reason they did it. Anyway, if you have access to a welder (thanks Verell!) it literally only takes 10 minutes to slap a quick couple of welds on all the bushings. That was probably the easiest part of the job!

    Birdman
     
  28. Dave

    Dave F1 Rookie

    Apr 15, 2001
    2,722
    Little Rock
    Full Name:
    David Jones
    Great work guys!
     

Share This Page