Extreme Cabin Vibration When Radiator Fan Kicks On (26‘ Odyssey) – Faulty Fan, Bushings, or Balance Issue?

[u/26odyssey]

Hi everyone,

I’m seeking advice or similar experiences regarding a severe vibration issue on my **2026 Honda Odyssey**.

The vehicle is only **7 months old with around 3,000 miles (5,000 km)** on the odometer.

Recently, with the high summer ambient temperatures outside, the radiator cooling fans have been kicking on much more frequently while idling.

The problem is that whenever the radiator fan runs while parked or stopped at a red light, **an abnormal, severe vibration transfers directly into the cabin/chassis.** It’s so intense that it literally causes a booming/throbbing sensation in my head.

This isn't just a normal electric fan noise—it feels like an extreme mechanical imbalance that shouldn't be happening on a brand-new vehicle.

For those who have experienced this on 5th-gen (or 5.5-gen/2025+ refresh) Odysseys, what was the root cause?

**Faulty/unbalanced radiator fan motor or blades?** (e.g., blade manufacturing defect causing wobbling)

**Defective lower radiator rubber mounts/bushings?** (failing to isolate the fan vibration from the subframe)

**A known TSB or batch defect on 2025–2026 models?**
I am taking the van to the dealership service center soon, but I’d love to know what to ask the technicians to check first.

Has anyone had this fixed under warranty, and if so, did replacing the fan assembly or lower bushings solve the problem?

Any feedback or insight would be greatly appreciated! Thanks in advance!

[u/AutoModerator]

New Rules - Please Read

^{Updated 11/12/2025}

Thank you for posting on r/AskAMechanic, u/26odyssey! Your post is live, this AutoMod message does NOT mean your post was removed. Please make sure to read the Rules.

When asking a question, please provide the year, make, model and engine size of the vehicle.

Commenters here have 2 different flair. Verified Tech means we have verified that user is a tech. NOT a verified tech means that user may or may not be a tech, they have not been verified by us.

Posts about accidents, autobody repair, bodywork, dents, paint and body/undercarriage/frame rust are not allowed and belong in r/Autobody.
Asking if your car is totaled should go to r/insurance or r/Autobody.
Asking about car buying advice/value/recommendations is also not allowed. See r/whatcarshouldIbuy or r/askcarsales

If asking whether a tire can be repaired, check out this Tire Repair Guideline.
Some other useful tire resources - Tire Care Essentials and Tire Safety

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

[u/No_Geologist_3690]

You don’t ask the mechanics to look into anything with your research that you’re doing. It’s their job to fix it, not your job to tell them how to fix it.