I have been meaning to replace my stereo forever. I need to do it. What do I need to know and any recommendations appreciated. I am not an audiophile but would spend more than a walmart unit. Thanks.

I replaced two 740s with crutchfield radios a few years ago.

DO NOT get the Kenwood KDC-HD262U . The display is unreadable in daylight on 700s. The controls are also very hard to navigate. I would imagine most Kenwoods of this vintage have the same issues with sunlight on a 740.

I spent a bit more and got Alpine's CDE-143BT . Much better display and controls.
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Paul NW Indiana '90 745 turbo 145 K

A favorite source for many of us is

Crutchfield Audio

Use the vehicle selector. Many popular and specialty radios to choose from at good prices and with an excellent reputation for customer service. If you find a model you like, google search that model number just in case somoene else, like on Amazon, has a better deal at the moment.

You will likely need to add to your purchase a dash kit consisting of a single DIN height mounting adapter and a suitable face plate bezel, as can be found with the vehicle selector.

For most standard applications, I'd recommend you get the associated plug&play wiring harness adapter from Crutchfield at the same time. Saves a lot of effort, but you can butcher up your existing harness and the new radio harness to splice them together if you want to save a few bucks. You would then need to know the wire colors and connector pin numbers. There are some here in the FAQ and others that google may be able to find. If needed, post back and someone may have the proper wiring diagram for your year.

I can't remember if your 740 has a separate pre-amp, some did, so if it does then you can get a radio that uses an external amplifier, otherwise just get a standard radio with a built in amplifier and disconnect the wire harness for any pre-amp that may be under the dash.

Once you get past MP3, USB, CD, iPhone, handsfree Bluetooth, satellite radio, etc. connectivity features, it's mostly a matter of deciding how wide you're willing to open your wallet in relation to your speakers and audio tastes. Once you get past the cheapest radios, speakers quickly become the limiting factor in listening quality. Lots of consumer reviews out there to help you.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Second the recommendation for Crutchfield. I did three replacement/upgrades with Crutchfield purchases, two in 740s , and they were completed in less than an hour.

They sell the install hardware and wiring harnesses as a kit, and as I recall, throw them in free with a lot of the head unit purchases. They also provide detailed printed instructions.

Have had way more trouble than anticipated. As recommended, ordered from Crutchfield, no problem. With the speakers in the front doors: on the driver's side, there was no speaker from day 1 (the hole in the door trim was not even cut out). I assume this was a mistake on the production line, really odd!! The size recommended by Crutchfield was 5.25, this is NOT the size of the original, which must be something like 5.75 (no longer available, apparently a discontinued size). So I called Crutchfield because of the space around the diameter, they sent me free baffling. The speakers BARELY have any trim to attach to, I hope they will stay in. Using a wiring diagram found on the internet, the door speakers are not getting sound. I will have to run new wiring to the "rear" wire output, since I have no rear speakers. The head unit was OK to install. The orginal in dash speakers are a molded unit. Once you disconnect, the wires are not long enough to re-connect, I cannot believe there is not a couple of extra inches. I will have to splice a few extra inches. Not sure how the new in-dash speakers will work, with the bigger magnets they will stick up some I think, and I have to cut out mesh speaker grill to fit. I'm wondering if my problems are unique to the year.

You seem to be having more than your share of radio problems.

Really weird. Missing driver door speaker? No hole in the door panel? But plastic speaker grill is presumably present? Hmmm, guess the radio installation crew on the factory floor went home early that day. Or is there any chance the door had to be replaced after an accident and the body shop didn't care to install a speaker? That actually might make more sense than the factory screwing up.

As for the rear door speakers, I assumed by 1991 all Volvo radios had quad speakers, but perhaps some of the base models still didn't, especially for certain markets. I know the 1989 240 DLs out of Halifax still didn't. My North American 1989 740 factory manual shows both standard and separately amplified radio wiring for USA/CAN/UK and all have rear speakers, no dotted lines to indicate variants. Is yours the base model, assembled in Halifax or Sweden? -if there's no decal then you may have to decode the VIN.

Before you go to all the effort of running new wires to the rear doors, the odds are high the main wiring harness to the rear doors already has speaker wires present. Maybe take a look at the radio harness under the dash. Now this is for a 1989 740, but the 1991 harnesses are likely the same or similar (a proper 1991 wiring diagram can likely be found on line with enough effort). Do you see two pairs of wires, one pair green & green/brown and the other pair yellow/brown & yellow/grey? In the radio connector they can likely be found opposite each other, like at pins 9&13 and 8&12 respectively. If not there, try following the wiring harness back to the two large main connection blocks, which may be rather inaccesible under the dash. One block is for the left side of car, one for the right. See if you can find them leading up to there, same colours, pins 35&36 in both connector blocks. Now if you can find those wires under the dash, the other end will be present in the connector blocks at the base of the B-pillars, saving you the trouble of having to run new wires to there. If you find them at the B-pillars, you might luck out and find them in the door harness, but they change colour to white & white/yellow (same for both rear doors).

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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

I just used Crutchfield to replace the unit in my 242.....and the one I'm replacing was supplied by Crutchfield 17 years ago!

I bought this unit -- https://www.crutchfield.com/p_158GS820BT/Sony-MEX-GS820BT.html It has a small amp built in -- 100W peak; 45 W RMS. CD capable as well as 2 USB inputs, bluetooth, etc. I spent money with the original system for decent speakers --- I'd recommend you do the same. The Crutchfield folks can help. I've got 3.5" Infinity 2-ways in the front door panels up high, and 6.5" Polk Audio 2-ways in the package tray. Really pleased with sound quality and clarity.

Have fun with the search.
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82 242-6.2L; '17 Mazda3; '16 Crosstrek