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PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
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PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft (Part Number: )
PST Carbon Fiber Driveshaft
Subaru STI 2015+
Read 7 Reviews | 8 Q&As
Part # IZS-1559

In stock! Ships same day

Features & Product Details

RallySport Direct is proud to provide you with alternative driveshaft options brought to you by PST. 

On this page, you are looking at the PST Carbon Fiber Driveshaft. This is a great way to help relieve some of the rotational mass of the drivetrain so that you can transfer more power to the wheels.

Here are more details:

  • Made using strong, and lightweight carbon fiber materials
  • Smoother launches as carbon fiber will twist, absorbing much of the drivetrain shock instead of putting all the stress on the differentials
  • Improved throttle response, acceleration, and braking
  • Weighs just over 14lbs
  • Specifications

    Brand: PST
    Material: Carbon Fiber
    Weight: 14.4lbs
    Mfgr. Warranty: 1 Year
    Condition: New Product
    Return Policy:

    RallySport Guarantee - 30 Days

    Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

    RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

    The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
    RallySport Guarantee



    7 Reviews
    4.7 out of 5 Stars
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Stars
    Customer Photos and Videos
    PST Carbon Fiber Driveshaft ( Part Number: IZS-1559)
    PST Carbon Fiber Driveshaft ( Part Number: IZS-1559)
    PST Carbon Fiber Driveshaft ( Part Number: IZS-1559)
    1 of 1 people found the following review helpful
    Best Mod with no downsides 12 months ago
    Wether your bone stock or modified, you'll wonder why this driveshaft didn't come from the factory with one. I've had my PST shaft on my 2016 Subaru STI for about a week and all I can say is, the jerky 1st to 2nd gear shifts are gone, the car revs much more freely, and starting from a dead stop is a breeze. It might just be me but I also feel as if the turbo is spooling up a couple hundred rpm's faster. This is honestly one of the few modifications that doesn't require a tune and has none of the drawbacks of noise, vibration, or harshness. The only drawback is the price, which is a little steep, but luckily I bought this when it was on sale during Black Friday. If your on the fence about buying this shaft, don't think DO IT!
    Was this review helpful?
    1 of 2 people found the following review helpful
    Carbon drive shaft 2 years ago
    The best modification for your car is the carbon driveshaft.The jolting in the drivetrain from the stock 2 piece steel shaft is terrible. The shifting transition as well is better,I feel the car acelleration now is more connected with the one piece shaft, the rotating mass loss is also an extra bonus to.Install is a breeze, just be careful when inserting the shaft into trans housing respect the seal there.
    Was this review helpful?
    1 of 2 people found the following review helpful
    Excellent Product, Couple Install Notes 2 years ago
    Greg B
    The "install video" here is inadequate. The process is straightforward, but there's more too it than what's in the video. It took me 90mins with hand tools. 1. Safely jack car up on stands or ramps, all four corners will make life easier. 2. Get working on the six bolts holding your mufflers to the midpipe, leave the last one barely on. Remove the hanger from the rubber bumper. 3. Loosen the two bolts on the forward end of the midpipe at the cat, be nice to your donut gasket, and drop midpipe to floor, remove last bold on muffler side. 4. Get to work on the four heatshield bolts. They're easy but the O2 sensor wire goes though it. I made a small cut the the heatshield instead of taking the sensor out. 5. Loosen and remove the four bolts on the rear diff side of the driveshaft, and have something to rest that end on, as the shaft won't flex enough at the midjoint to touch the floor. Move on to the two large bolts at that mid joint and get ready to hold 30+lbs . Supporting the whole driveshaft, pull it out of the transmission, some fluid will leak. 6. Before reversing this process, put some grease or something in the spline of the new one. The four bolts you're reusing? Those heads are round with one flat side, to rest against a flat edge of the old knuckle. That doesn't work on the new one, you'll need an open ended wrench to hold them from spinning, while you tighten the nut. If you are re-using those crush washers, add some loctite and let it cure 24 hours. When you install the new shaft, you'll have to line it up on the spline, so that all four holes on the rear diff match. Or if e-brake is off, maybe just turn it. 7. Re-install heatshield, re-attach midpipe. You're done.
    Was this review helpful?
    1 of 1 people found the following review helpful
    PST CF DS 3 years ago
    Kyle F.
    Had mine done yesterday at Cobb. Less arguing with the clutch leaving 1st and id agree with others the car revs better through the gears. No improvement on NVH unless your old shaft was loose/carrier bushings shot. PST makes other shafts for other cars with $125 forged aluminum yolk upgrades and these scoob shafts only come in steel yolk, didnt see an aluminum upgrade on PST site to get weigh down to 12lb(??) Im assuming they have a pricing deal worked out through RSD w the steel yolks. YT 'boostaholics PST GC8' that vid he visits PST shop in Clearwatee and you can see our shafts with shiney yolks like the DSS but they spray em all black before shipping. Ive read rumor on forum DSS supplies them w the CF bores but that may be wrong? No buyers remorse except the wife found out and shes pissed lol.
    Was this review helpful?
    Love this driveshaft 3 years ago
    Rick C.
    Such an underrated modification. Smooths out drivetrain noise and harshness, allows for better launches, and reduces weight. There are very few mods with no downsides, but this is one of them. Highly recommended.
    Was this review helpful?


    • Q: custom order  chrisb_one8 months ago

      would I be able to order this drive shaft with the forged aluminum yolks vs the steel yolks? I'm concerned about the rusting from the steel yolks as someone else has stated.
      • 0 of 0 people found the following answer helpful

        A:  On any kind of custom order it's a case by case basis. You would need to reach out to our customer service department at 888-45-Rally!

        Megan L. @ RallySport Direct 6 months ago  
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    • Q: PST Carbon Fiber Driveshaft  eschellerup1 year ago

      I read online that the DSS CF driveshaft comes with larger bolts that hookup to the rear diff and a workaround is needed to make it fit with the supplied hardware. With the PST, is that needed or it a direct fit with supplied or with original re-used hardware?
      • 0 of 0 people found the following answer helpful

        A:  Hardware is not included, this is intended to be installed the the original hardware on your vehicle and would be a direct install.

        Evan M. @ RallySport Direct 1 year ago  
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    • Q: Carbon Fiber Driveshaft  tonytony1 year ago

      Does the PST Carbon Fiber Driveshaft fit JDM version of STI (model: VAB, EJ20)? thanks
      • 0 of 0 people found the following answer helpful

        A:  We cannot confirm these to fit anything other than USDM models. However, we can have PST make you a custom one. Please contact [email protected] for more info.

        Tyler A. @ RallySport Direct 1 year ago  
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    • Q: Driveshaft   Mitchell 2 years ago

      Is it safe to launch your car with this shaft ?
      • 0 of 0 people found the following answer helpful

        A:  Launching your car is never considered safe, however this driveshaft is designed to a huge amount of power compared to stock.

        Jared A. @ RallySport Direct 2 years ago  
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    • Q: PST carbon fiber driveshaft for sti  donaldrey6846092 years ago

      How much horsepower will this carbon fiber driveshaft handle? Car has 516hp right now but planning on getting around 600-650hp soon