Drivetrain› Differentials and Rear-End Components
DETROIT SPEED ENGINEERING
FN988 STD Case 31 SPL TT 3.55 Ratio 1350
SKU: D03M 070880-355DS
Moderate — 2–4 hours
Description
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Fitment
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Specifications
| Brand | DETROIT SPEED ENGINEERING |
| Part Number | D03M 070880-355DS |
Videos
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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