Because existing sources of auto reliability information left much to be desired, in late 2005 I started conducting my own reliability research at TrueDelta.com. TrueDelta reports absolute stats like "trips to the shop" that make the differences between cars much clearer. Results are updated four times a year, so it's possible to provide reliability information on new models quickly. Also, any significant changes in a model's reliability become apparent quickly.

So far, 208 Corollas have been enrolled to help out with this research. This has enabled me to start collecting data on a couple of model years, but for these and other years more participants are needed.

Participants simply report repairs the month after they occur on a one-page survey. When there are no repairs, they simply report an approximate odometer reading four times a year, at the end of each quarter.

To encourage participation, panel members will receive full access to the results for free.

For the details, and to sign up to help out:

Auto reliability research

224 Corolla owners have signed up to help so far. A good start, but hundreds more are needed.

2003 and 2007 are close to the minimum needed to get started, while 1999, 2005, and 2006 are just above the minimum.

Always looking for more participants. Next set of results in Early February.

Those results were posted. Only one model year included for the Corolla, the 2005, with no repairs reported by 17 responding owners.

More participants very much needed for all model years. We'd like to include as many as possible in future updates, with the next one in May.

For the details, and to help get the Corolla included:

Vehicle reliability research

About to start the last month of data collection before the May update.

Help get your year included:

Vehicle reliability research

If you've signed up to participate but haven't yet responded to the survey (via a link in the email you received), please do. And if you haven't signed up yet, I hope you'll consider doing so. I'd really like to have more than one model year of the Corolla in May.

Vehicle reliability research

Next update in August.

Additional participants needed for all model years--for many of them, an extra response could make the difference between having a result and not having one.

To help get your year included:

Vehicle reliability research

Those results soon. Additional responses still very helpful.

Vehicle reliability research

The 2005 and 2006 will be in the upcoming results, though with asterisks for marginal sample size.

Many other years are two or three responses short of the bare minimum.

I'd like to include all years, without any asterisks.

To help make this happen:

Vehicle reliability research

Those results have been posted. But the sample sizes are small, so they are asterisked and only visible to members on the site itself. Worse, they do not appear to be accurate--owners reported few repairs for the 2005 but an above average number for the 2006.

More participants are needed to provide more precise results and cover additional model years.

TrueDelta Vehicle Reliability Survey results