Q:

Irregular Verbs in first and third person plural

For a regular German verb, the infinitive, first person plural and third person plural are the same - e.g. fahren; wir fahren; sie fahren.
For almost all of the common irregular verbs I've seen, this also seems to be the case - e.g. haben; wir haben; sie haben.
Sein is an exception, but even here the first and third person plural forms are the same - sein; wir sind; sie sind.

Are there any other irregular verbs in which the infinitive and first/third plural forms differ?
Are there any verbs in which the first and third person plural forms differ?

A:

To put it simple, the infinitive, first and third person plural present tense are the same for all verbs but sein. The first and third person plural are identical in their respective tense/mood for all verbs.
There aren't too many really irregular verbs in German either. The most of those you see as irregular are strong verbs, which also follow one of seven patterns (which you should not learn, by the way.)

A:

Well, for verbs with separable particles the infinitive will differ, regardless of the irregularity. 
E.g. einladen - wir laden ein, sie laden ein. But that is somewhat nitpicky as they generally can be simplified to the word without particle (laden), even if that word might be archaic by now. 
A similar case exists for reflexive verbs. sich erinnern - wir erinnern uns, sie erinnern sich. Again, the second part changes, but it feels like cheating..
Otherwise, I cannot think about an example apart from sein. 

