I spent a long while looking for 4" speakers that fit well in my 84 300td, and the answer was pretty much: good luck. There was a good Boston acoustics speakers that's expensive and discontinued, and not much else. I did some searching, my initial screening was looking at pictures for what would clear the speaker grill, after that I found datasheets to look at measurements. Took detailed measurements of the speaker hole and found one that would pretty much just drop it.

The Rockford Fosgate R14X2 Prime 4-Inch Full Range Coaxial Speaker are almost a perfect fit.



As can be seen in the picture, only the foremost tab has to be cut off, the rest can stay. Careful measurement paid off and the mounting hole in the one tab lines up perfectly with the screw that holds on the speaker grill! Success!

The only other modification is cutting down the standoff on the grill itself, since it now has to sit on the speaker mounting tab the grill sits just a touch high in the back.

I lobbed about 1/8" off with a sharp pair of dykes and put it all back together.

I'm not audiophile, but nothing sounds as good as my old dynaco st70 after I fully rebuilt it... However these speakers sound pretty good. I listen to a lot of classical which really tests the dynamic range of speakers, and I'm quite happy. For $33 speakers and 20 minutes to install them including soldering and modifying, I'm happy.

hi,
thanks for sharing,
so you were able to put the original grills back on, and not the ones that come with it on the amazon link you shared... but they sit higher than normal?
do you have a finished photo you can share?

how is the base on them?
the car i purchased, an 85 300d turbo, the previous owner said he put the best speakers he could in them, infinity i believe, but that due to the size that's possible, the bass isn't so great. i'm not looking for crazy bass, just a normal amount, which i don't feel i have.

i was considering putting in an under the seat subwoofer but if these are better that would be great.

The stock grills went on after I cut the standoff (where the only screw goes through) down just a touch. The final installed picture looks completely stock. The bass isn't great, they're 2-way 4" speakers, pretty much condemns any low end response. The lower mids through highs sound really good, though. I'm impressed.

I don't know what the 300d uses for rear speakers, but the wagon uses something common like 6" (can't remember off the top of my head), so there are a lot of options there.

hmmm, i guess my previous 2 door car had at least 4 6.5" speakers, and the bass was good on that, i have to check what speakers i have in right now, but it looks like 3.5"-4" in front and 4-5.25" in back of the 300D might not create enough bass to be comparable,

it's like you can't hear the bass guitar or bass drum on some songs...

I also put Rockford Fosgate speakers of the appropriate size in the back and I'm happy with the results. Everyone has a different taste for music and sound quality, though. Depending what you listen to greatly impacts what kind of audio system you need.

Even a small amplifier can make a big difference depending on how nice your head unit is.

so it looks like the previous owner of my 300D turbo also put in 4" speakers in the front, cutting off 1 of the 4 mounting tabs, but the speakers he chose look like they protruded higher than the grills would allow. he had a faux suede front dash cover that goes over the speakers, and it's light so it doesn't seem to affect audio quality.

in the first picture attached, i measured diameter to the outer edge of the circle and it was 4 inches.


for the rear, they say infinity kappa, they're 6" diameter measured to the outer edge of the grill circle, so i'm not sure which kappa model they are.
they do stick up a bit and look a little strange but i guess i'll get used to it.

i'm on the fence on whether or not a subwoofer is necessary for a good dynamic range, but it probably is.

are people putting larger than 4" on their fronts by modifying the dash and just covering it with a dash cover?

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I think I saw a post somewhere about modifying the dash to accept a bigger speaker. I didn't want to do that so I went on a search to find speakers that fit.

This is a good find!!

I'm curious if these speakers are held down by more than one screw though. I get it that the speaker grille screw works and aligns, but do any other holes? Must another screw be used in one of the other three locations?

Did you use the OE connector via an adapter, or just butt splice or solder wires together?

Thanks!

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Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (116k)
1991 350SD (206k)
1991 300D (228k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (267k)

Past Diesels:
1983 300D (228K), 1985 300D (233K), 1993 300D 2.5T (338k), 1993 300SD (291k)

I'm pretty sure the front of the grill hits the cutoff area of the tab and helps hold it down. Either way, I don't have any rattling or buzzing. If you did, you could just get some stick on weather stripping and put it around the metal case of the speaker, the grill would rest on that holding it in place.

I cut the wires off the old speakers and soldered them onto the new speakers. That way they plug into the wiring harness like stock and I didn't have to butcher any car side wiring.

Old thread, I know. But this looks like a nice option. Thinking seriously about pulling the trigger on these. Anyone found any other options out there? Seems like the key is a flush mount coax tweeter. Becker sells some on ebay, but the price is outrageous for a relatively cheap speaker out of germany. Only reason they get away with it is that they're difficult to get here in the states.

I have the 4 inch Boston Acoustic speakers in the dash and put 6 1/2 inch , 3 way Pioneer speakers in the rear deck of my '82 300D and the sound was rather thin on the bass end. So I added a powered subwoofer that sits in the left trunk recess. By removing the first aid kit from the rear shelf, I am able to enjoy the bass feeding from the trunk.This setup has survived for 12 years and predates the easy availability of thin,underseat subwoofers which I believe would sound better.

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Gwizzer
'82 300D

I miss radio shack, where you could find all sizes.Even get 2 ohm speaker,that made a stock system like a 100 watts

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1999 w140, quit voting to old, and to old to fight, a god damned veteran, deutschland deutschland uber alles uber alles in der welt