A Critical Issue on Porsche Boxster 986 cars, made before 2003, is dealing with a Cracked Porsche Boxster Rear Plastic Window
Porsche produced the original Boxster with a plastic rear window. The lifespan of the plastic window can be quite low. You need to be careful of both “cold crack” and scratching problems.
In 2003 Porsche upgraded the Boxster to a glass rear screen, however, they changed the pattern at the same time making it impossible to upgrade the old cars with the new convertible top. The new OEM convertible top with a rear glass window, can not be retrofitted onto pre-2003 Boxsters.

Care for Your Rear Plastic Window
If you own a Porsche Boxster 986 with a rear plastic window, you need to be extra careful. Here are some tips for increasing the lifespan of your rear plastic window.

Pedro has had his 1998 Boxster rear plastic window last over well over 20 years.
1.0 Do Not Lower the 986 Convertible Top in Cold Weather
Be very careful when opening your convertible top in cold weather. The colder the weather the more prone your plastic rear window is apt to crack. Never operate the convertible top under 55ºF (or 12°C) without a thorough warm-up.
Newer plastic rear windows are very pliable but age sees the rear plastic windows get brittle and inflexible.
Never use your convertible top below 40°F or 5°C!
2.0 Boxster Chop
All owners of a 986 with a rear plastic window need to learn the “Boxster Chop”. You need to get your black belt in this critical defensive maneuver.
When you do lower the top, open the top enough to start the rear window folding then get out of the car and do a ‘chop’ with your arm/hand and make a nice even crease/fold in the window so when you open the top all the way the window doesn’t develop a compound fold/crease.
The “Boxster Chop” is recommended in all weather conditions as a defensive measure.
3.0 Yearly Maintenance of Rear Place Window
If you have a rear plastic window on your Porsche Boxster you need to take extra special care of it. You need to clean and polish it yearly to prevent oxidation (or yellowing and pitting.)
3.1 Clean and Protection of the Rear Plastic Window
The plastic rear window will fog and scratch which is one of the biggest complaints from Boxster owners. Fogging and oxidation happen as the plasticizers evaporate. This is caused by UV Light and the heat from the sun. As a result, the Boxster’s Rear Plastic Window becomes cracked or damaged.
The best way to maintain your plastic rear window is to keep the sun off the plastic rear window as much as possible. Use a good plastic cleaner and UV protectant.
Preview | Product | Rating | |
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Plexus Plastic Cleaner, Protectant and Polish (13-Ounce) | 6,191 Reviews | Amazon |
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CAR GUYS Plastic Restorer | Bring Plastic, Rubber, and Vinyl Back to Life! | User Friendly Trim... | 28,718 Reviews | Amazon |
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303 Aerospace Protectant – UV Protection – Repels Dust, Dirt, & Staining – Smooth Matte Finish... | 12,760 Reviews | Amazon |
3.2 Polish Your Rear Plastic Window
Rid your read plastic window of minor scuffs, yellowing, and scratches using good plastic polish. Your rear plastic window can be restored using a plastic polishing compound.
Preview | Product | Rating | |
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Meguiar's PlastX Clear Plastic Polish, Fast & Easy Plastic Restorer for Headlights, Taillights, Soft... | 14,324 Reviews | Amazon |
Repair Options for your Porsche Boxster Rear Cracked Plastic Window
1.0 Seal the Crack ASAP on Your Plastic Window
Once you notice that your rear plastic window is cracked, you need to act immediately to prevent further damage. Minimize all use of your convertible top until you choose an option to repair the issue.
1.1 Quick Fix for Cracked Rear Window
It is important to seal your cracked window ASAP. You do not want the crack to spread or cause more damage. Lamin-X has a dedicated Convertible Plastic Window Repair solution. Very durable and will stand up to time. It comes with a 5-year warranty.
- Clear 2" x 24" Universal Adhesive Film
- Glossy finish for high-quality look
- Made in USA, 5-year warranty, industry-leading product
- Transparent film that adheres directly onto your soft window
2.0 Replace the Rear Plastic Window
Many forum Porsche Boxster members have reported excellent service for the rear plastic window from Boat Canvas Repair service shops. All boats make use of canvas covers with plastic windows. Many drivers have received cost-efficient solutions for a quick repair or replacement of the plastic window.
Boat Repair can replace the plastic window at a reasonable price.
3.0 Repair Worn, Torn, or Damaged Convertible Canvas
This is a preferred option if you get your canvas cut because of theft (or break and enter of your car.) These shops can do a quick waterproof seal to your canvas roof.

It is critical that you need to get this on quickly to prevent the holes or tears from spreading. Your fastest and best solution would be to use a canvas patch. We recommend that you would use a Gore-Tex canvas patch. You need a 1/2 inch over coverage on the patch and you can cut to size to minimize the size of the patch.
# | Preview | Product | Rating | Price | |
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1 |
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GEAR AID Tenacious Tape GORE-TEX Fabric Patches for Jacket Repair, Black, Round and Rectangle ,3”... | 2,825 Reviews |
$11.50 |
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2 |
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4 Pack Waterproof Iron-on Repair Patch (3"x9") for Gore-tex Drysuit Like Fabric | 53 Reviews |
$19.95 |
Amazon |
3 |
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5 Pack Waterproof Iron-on Repair Patch (3"x3") for Gore-tex Drysuit Like Fabric | 17 Reviews |
$17.95 |
Amazon |
Make sure you get a quote and compare any previous work of the shop.
4.0 Replace the Rear Plastic Window with Glass
For this option, you will need to investigate using a car service repair shop that specializes in convertible tops. I have to warn you though, that the cost for this repair will almost always exceed the cost of the next and preferred option of replacing the entire top..
When getting this quote, also ask for a complete replacement of the top as well. This will give you a good comparison. Please note that the replacement of the rear window will still be the same size and not larger as seen in the post 2003 Boxsters.
5.0 Replacing Your Porsche Boxster Convertible Top
Many 986 owners opt to get a new canvas top, complete with a new glass window. If you’re looking to buy an early Boxster 986, please keep in mind this upgrade and the costs involved.
- 1 Year Manufacturer Warranty
- Canvas Cloth
- Window: 50 Gauge Heavey Plastic window like the original
- This top comes completely assembled and ready to install. No sewing is required
- Canvas Cloth
- DOT Approved Heated Glass Window.
- This top comes completely assembled and ready to install. No sewing is required.
- Our tops are Brand new in the original box.
All Boxster Forum Sites will have multiple dedicated threads on this issue and offer many solutions for resolution.
Please note that Replacing the Convertible Roof is Project 70 in the 101 Projects for Your Porsche Boxster.


6.0 From Amazon
- Haartz TwillFast RPC acoustic canvas
- Provides up to 2dB (noticeable) noise reduction
- Defroster, tinted glass window upgrade
- No Stitching or Piping around window
- 5 year warranty to original owner
- Repair Kit Includes: 2 X Pors 986 987 Box-ster Convertible Top Push Rod Ball Joint
- The Plastic used is the mixture of glass fiber which i heat resistance and durable.
- Pors che Applications: Box-ster (1997-2012)
- Repair Kit Includes: 2 X Porsche 986 987 Boxster Convertible Top Push Rod Ball Joint
- If you own a Porsche 986 Boxster, more than likely your convertible top will suffer from the infamous broken plastic push rod end. Porsche used a plastic end on the push rod used to operate the convertible top. These plastic ends are notorious for breaking and unfortunately can set you back $150 if you have to buy 2 new push rods since the dealer does not sell the plastic end piece separately.
- The Plastic used is the mixture of glass fiber which i heat resistance and durable.
- Porsche Applications: Boxster (1997-2012)
- Canvas Cloth
- DOT Approved Heated Glass Window.
- This top comes completely assembled and ready to install. No sewing is required.
- Our tops are Brand new in the original box.
- 🚗【APPLICABLE VEHICLES】Compatible with 1997-2012 Porsche Boxster. Please check the vehicle model carefully to ensure that it is consistent with your vehicle parts
- 🚗【REPLACEMENT NUMBER】REPP351802, 98656127902, 98756127900. Please carefully check whether the replacement oe number and applicable vehicles is consistent with your convertible top rod parts to avoid an unpleasant shopping experience!
- 🚗【PLATINUM QUALITY】All convertible top rod undergo rigorous testing before being sold. Easy Installation, very durable ensure has a longer lifespan
- 🚗【HIGH PERFORMANCE】This Convertible Top Rod built according to the highest standards of quality and precise specifications, which is more reliable and stable
- 🚗【AFTER-SALES SERVICE】When you receive convertible top rod products, if you have any questions, please feel free to contact us, we will solve the problem for you within 35 hours
- Top Transmission Gears L+R Side Compatible With Porsche Boxster Convertible 1997 to 2012 98756118001
- OEM Numbers (Only for Comparison): 98756118001
- Compatibility: Porsche Boxster Convertible 1997 to 2012
- Important: Please compare your parts with the pictures before purchasing an item.
- Package Included: 1x Top Transmission Gear Set (L+R)
- Upgraded German A5B/DS Acoustic Cloth / Canvas for superior sound dampening
- Entire top is cut from the same bolt of cloth for consistent color and pattern
- Slightly tinted heavy gauge press-polish plastic window for superior visibility
- Includes the wiring harness to connect the defroster window to electrical system
- Flush mounted deck seams like original and unique to these Boxsters
- Garage-Pro Aftermarket Replacement Compatible with 1997-2004 Porsche Boxster
- Garage-Pro JCWREPP351801GP Features: Sold individually
- Location: Driver or Passenger Side
- Replaces OE Number: 98656127902
- A high quality, Direct Fit OE Replacement Convertible Top Rod with FREE 1-year UNLIMITED mileage warranty coverage on Garage-Pro items.
- First quality Twillfast II cloth with a dobby weave lining
- Precision cut with Gerber automated computer guided cutting equipment
- DOT approved plastic window same as factory original
- Includes new steel side hold down cables already securely installed on this top
- Factory-style retainer attachments are sewn-in for an easy & accurate installation
7.0 From the Internet:
Top 5 Recommended Boxster Web Forums (Excellent Resource for repairs and advice)
6SpeedOnline – Rear window ripped, now what?
PedrosBoard – Rear window replacement question for 986
8.0 Be Sure To Join Our FaceBook Group

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Last update on 2023-12-09 / Affiliate links / Images from Amazon Product Advertising API