Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
Welcome Offer : Use Code WELCOME5 for 5% OFF!
Free Shipping on Most USA Orders
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For more information, visit www.P65Warnings.ca.gov.
Complaints: Burnt clutches & bands and poor shift quality. Cause: Wear at the piston pin bore due to repeated reciprocation. Correction: The Sonnax patented pinless design with dual seals stabilizes the piston in the bore and provides improved sealing characteristics. Use of the Sonnax part eliminates the need for the pins. In GM 4L60-E, 4L65-E and 4L70-E units it is common to have poor shift quality, burnt bands or clutches due to accumulator piston wear. Repeated reciprocation of the accumulator piston causes wear at the piston pin bore interface. After this wear reaches a critical point, fluid loss through the piston pin bore cannot be compensated due to lack of pump volume. In addition, the piston can get cocked and gall the accumulator bore due to the pin bore wear or the spring bottoming out. To prevent these conditions in the 1-2 or 3-4 accumulator bores, Sonnax offers pinless accumulator piston kit 77998-03K.
I used the Sonnax pinless accumulator piston kit for my 4L60E rebuild and it worked like a charm. The installation was pretty straightforward and the pistons fit perfectly. Definitely improved the shifting performance, which was a bonus!
E
Elena Rodriguez
Decent Kit with Minor Issues
The Sonnax kit is solid overall, but I did have a little trouble with the instructions. They could be clearer, especially for someone who’s not super experienced with transmission work. Still, it did the job once I figured things out!
L
Linda Nguyen
Not What I Expected
I had high hopes for this kit, but unfortunately, the piston didn't fit my 4L70-E properly and I had to return it. The delay in shipping didn't help either. I might just stick to OEM parts next time.
R
Raj Patel
Fixed My Shifting Problems
The Sonnax pinless accumulator piston kit has really helped with my 4L65-E transmission. Shifts are smoother now, and I appreciate how durable the parts feel. Worth the investment for any DIYer tackling a rebuild!
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Is the shipping free?
Yes, we offer free standard shipping on all orders within the United States.
When will I receive my item?
Domestic orders typically arrive within 3-5 business days. Delivery times are estimated and may vary depending on your location, weather conditions, or other unforeseen factors.
Can I change or return my item?
We hope you love your purchase, but if you need to make a change or return your item, we’ve got you covered! You can initiate a return or exchange within 30 days of receiving your order. Please ensure the product is in its original condition and packaging. For more information on our return policy, please visit our Returns & Exchanges page.
