Chevrolet Sonic: 6T30 or 6T40?
Both answers can be correct, depending on the exact Sonic application. GM Safety Recall 14234A supports the 2012 Chevrolet Sonic 1.8L LUW automatic as 6T30 with RPO MH9. GM PIP5353F supports 2012–2020 Chevrolet Sonic 1.4L LUJ/LUV automatic applications as 6T40 with RPO MH8. That is why “Chevrolet Sonic” by itself is not enough to identify the transmission.
The evidence in one table
| Application supported by the evidence | Transmission | RPO | Evidence |
|---|---|---|---|
| 2012 Chevrolet Sonic 1.8L LUW automatic | 6T30 | MH9 | E101 · GM Safety Recall 14234A / DCS3342 |
| 2012–2020 Chevrolet Sonic 1.4L LUJ/LUV automatic | 6T40 | MH8 | E104 · GM PIP5353F |
The useful conclusion is not that one source is “right” and the other is “wrong.” They describe different Sonic applications. The model badge stays the same while the supported engine/transmission pairing changes.
What does GM evidence support for the 2012 Sonic 1.8L LUW?
E101 [Manual] is the narrowest row in this article. The GM recall document identifies the 2012 Chevrolet Sonic 1.8L LUW automatic with 6T30 / RPO MH9.
The year boundary matters. This evidence supports the exact 2012 application. It does not authorize us to publish “all Sonic 1.8L vehicles use 6T30” or to extend the same mapping into later model years without another source.
That limitation is deliberate. A precise one-year application is more useful than a broader fitment statement created by extrapolation.
What does GM PIP5353F support for the Sonic 1.4L LUJ/LUV?
E104 [Manual] supports a different Sonic application: 2012–2020 Chevrolet Sonic 1.4L LUJ/LUV automatic = 6T40 / RPO MH8.
This gives us the key counterexample for model-name-only fitment. In 2012 alone, the evidence set contains a Sonic 1.8L LUW automatic mapped to 6T30/MH9 and a Sonic 1.4L LUJ/LUV automatic family mapped to 6T40/MH8.
So a search such as “Chevrolet Sonic transmission” is under-specified until the engine/application is resolved.
Why the model name alone is not enough
A vehicle model can span multiple engines, years and transmission configurations. For the Sonic evidence above, engine/application changes the answer from 6T30 to 6T40.
This is the same fitment-control principle explained in our methodology article: why a listing title or model name is not enough for transmission fitment.
- Identify the exact model year.
- Identify the exact engine/application.
- Verify the transmission/RPO from a source that makes that mapping explicitly.
- Only then move to an exact part-number decision.
This article stops at step 3. It does not select a filter, seal or overhaul component.
Why we do not expand broad bulletins into extra Sonic combinations
E112 is a methodological guardrail: a broad GM bulletin that lists many vehicles and several 6T-family transmissions together cannot automatically be split into one exact transmission mapping per model unless the document gives that row-level relationship.
That means we do not use a large “Sonic appears somewhere in a 6T bulletin” list to manufacture additional year/engine combinations. The two fitment rows published here are the combinations for which the current evidence set supports the mapping at the required level.
Does this tell me which filter or seal to buy?
No. Transmission identification and exact part selection are different intents.
Knowing that a supported application is 6T30 or 6T40 narrows the problem, but it does not prove an exact filter, seal or gasket number for a particular vehicle. Generation, exact application and the target component still need their own verification.
If your separate question is specifically about the two 6T30 filter records 24237508 vs 24268086, use the dedicated 6T30 filter-generation article. This Sonic article does not duplicate that selection answer.
Evidence boundary
| Evidence | Supports | Limit |
|---|---|---|
| E101 · GM Safety Recall 14234A / DCS3342 | 2012 Sonic 1.8L LUW automatic = 6T30 / MH9 | Exact 2012 application only |
| E104 · GM PIP5353F | 2012–2020 Sonic 1.4L LUJ/LUV automatic = 6T40 / MH8 | Do not convert unrelated bulletin rows into extra mappings |
| E112 · fitment method | Broad multi-vehicle/multi-transmission tables require explicit row-level mapping before publication | Methodological guardrail, not a new Sonic fitment row |
What we do not claim here
We do not claim every Chevrolet Sonic uses 6T30.
We do not claim every Chevrolet Sonic uses 6T40.
We do not extend the 2012 Sonic 1.8L LUW → 6T30/MH9 row into later years.
We do not infer additional Sonic combinations from broad multi-vehicle bulletins.
We do not publish country/market coverage that the cited evidence does not establish.
We do not select a filter, seal or gasket in this article.
Frequently asked
- Does every Chevrolet Sonic use a 6T30?
- No. The evidence set supports the 2012 Sonic 1.8L LUW automatic as 6T30/MH9, but supports 2012–2020 Sonic 1.4L LUJ/LUV automatic applications as 6T40/MH8.
- What transmission is supported for the 2012 Sonic 1.8L LUW automatic?
- GM Safety Recall 14234A supports 6T30 with RPO MH9 for that exact 2012 application.
- What transmission is supported for the Sonic 1.4L LUJ/LUV automatic?
- GM PIP5353F supports 2012–2020 Chevrolet Sonic 1.4L LUJ/LUV automatic applications as 6T40 with RPO MH8.
- Can I extend the 2012 Sonic 1.8L 6T30 result to later model years?
- Not from E101. Its publication boundary is the exact 2012 Sonic 1.8L LUW application, so later years require separate evidence.
- Can the Chevrolet Sonic model name alone identify the transmission?
- No. The supported 1.8L and 1.4L applications above resolve to different transmissions, so engine/application information is required.
- Does this article tell me which Sonic filter or seal to buy?
- No. It identifies supported transmission mappings only. Exact part selection is a separate verification task and is intentionally not answered here.