Rennlist

C4 tire options

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Original source

1 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHC4 tire options

Leading reported evidence

Run tire combinations outside of the front

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
So, can I run tire combinations outside of the front to back ratios that came stock?
Original post Read captured discussion
C4 tire options

Frequently discussed work

Replace wheels

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
I am replacing the wheels with 8s and 10x18s (turbo twists).
Original post Read captured discussion
C4 tire options

Read full discussion summary

Leading evidence: 'Run tire combinations outside of the front' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace wheels' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

Read captured replies

1 matching discussions · 1 captured posts examined · 0 partial discussions

Compare 3 other evidence results

Use 225x40 fronts, and 285x30 rears

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
The later C4s (2003 I think) used 225x40 fronts, and 285x30 rears.
Original post Read captured discussion
C4 tire options

Replace wheels

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
I am replacing the wheels with 8s and 10x18s (turbo twists).
Original post Read captured discussion
C4 tire options

Run 235x35 fronts and be just about bang

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
If I wanted to keep the same circumference ratio as now, I could run 235x35 fronts and be just about bang on what the ratios are now front to back, although they both would increase height and circumference moderately.
Original post Read captured discussion
C4 tire options

Frequently discussed actions (4)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Replace wheels

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
I am replacing the wheels with 8s and 10x18s (turbo twists).
Original post Read captured discussion
C4 tire options

Run 235x35 fronts and be just about bang

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
If I wanted to keep the same circumference ratio as now, I could run 235x35 fronts and be just about bang on what the ratios are now front to back, although they both would increase height and circumference moderately.
Original post Read captured discussion
C4 tire options

Run tire combinations outside of the front

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
So, can I run tire combinations outside of the front to back ratios that came stock?
Original post Read captured discussion
C4 tire options

Use 225x40 fronts, and 285x30 rears

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that performed work without a confirmed outcome: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Performed · outcome unconfirmed · Original poster
The later C4s (2003 I think) used 225x40 fronts, and 285x30 rears.
Original post Read captured discussion
C4 tire options

Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

1 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261027T005001Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I have a 99 C4 and it came with 7.5" and 9" x 18 turbo twists with 225 40 18 FT and 265 35 18 rears (Continentals SportContact 2). I am replacing the wheels with 8s and 10x18s (turbo twists). I know that the C4 is sensitive to tire sizes front to back, as the rotation difference determines the amount of differential lockup. The later C4s (2003 I think) used 225x40 fronts, and 285x30 rears. Is that model year specific, as in the later models are programmed differently? Or is that a permissible amount of difference in circumference (the 285x30s actually have a smaller height and circumference than the fronts). Also, I have a friend at a Mercedes dealership, and he has offered me a free set of brand new SportContact 2's in 275x35x18 that were take-offs (E55 I think). If I wanted to keep the same circumference ratio as now, I could run 235x35 fronts and be just about bang on what the ratios are now front to back, although they both would increase height and circumference moderately. But that would also keep the rears slightly taller than the fronts, which seems like the right look. So, can I run tire combinations outside of the front to back ratios that came stock? And do you think the 275's are a good choice, either with 225x35 or 235x35 fronts. I know Continentals would not be most people's choice, but the price is right. Tony

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