My light trio has been on for just a bit, the issue that concerns me along w/ this; is the clicking noise that comes when I give it a fair amount of gas from a stop. If i gently press the gas ( which I normally do) there is no issue, but if I have to get more speed up immediately and push the pedal kinda hard the vehicle takes off, but there is clicking sound( like the transmission is slipping but I don't believe this is the culprit). I replaced the brakes a while back using (i believe) mintex pads and brembo rotors. I usually only replace w/ high end parts.
97 RR 4.6

 

You say light trio, which lights ? ABS ? TC ? CHECK ENGINE ? GEAR BOX ?
You need to get codes checked .
If your clicking is from your transfer box , stop driving the vehicle, a quick test : in gear hold your foot on the brake. now give it some gas,if you get that loud ratchetting noise (clicking) you will need a new chain in your transfer box. I recomend to not drive the vahicle if this is the problem, because you can blow out your transmissions one way sprag.
The t-box can be overhauled by a good trans shop, borg warner parts are cheaper there than at a dealer.
Nothing has happened here except normal wear, these chains stretch alot as the miles pile up, I've seen it as low as 85k to most over 100k miles.
Also if the diagnosis is correct you would get the trio of lights because when the t-box chain slips the engine and trans ECU's see different input andoutput speeds.

 

On average; how much are we talking?

thanks

 

dirtyduk's diagnosis is most likely, ... scared to hear how expensive that might prove to be!

additionally though, my friend had a similar noise from his vehicle, (though he made no mention of any lights!)
- his problem was solved by replacing the universal joints on the prop shafts.

not likely this time by the sound of it...
good luck

 

Yup, test proved positive. In gear and given gas....noise.