Bubbles in a 134a system do NOT necessarily spell a need for parts. Bubbles are normal in a 134a system.

Dealer cost for R/D and TXV valve ~$160
FastLane less than 1/2 that. 134a is cheap. `$440 buys a lot of very skilled labor. They better fix it right the first time for that fee, if they are claiming R/D and TVX is the cause. I would insure that they did/do a VERY thorough leak testing!!

Do NOT do a routine service of recovery/vacuum/recharge on a working A/C system. (assuming no problems). Opening an A/C system is what can CAUSE the problems. I have NEVER heard of (and I've been around) a routine recovery/recharge every three years (say: "revenue generator").

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The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)