I have a small boat, tho the trailer design makes it a bit hitch heavy ---- maybe 90 lbs ...... I don't want to go to air shocks as I will be giving up the competence of Bilsteins for the rest of my driving (99%) ---- anybody have any experience fitting air bags inside the coils & filling as needed from a compressor (which I have)?

That's going to be a challenge; aren't the shocks on a W123 located INSIDE the rear coils?

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Never a dull moment at Berry Hill Farm.

I wouldn't fool with the car for 90 lbs of tongue weight. Don't know your boat rig, but tongue weight should be about 10% of total loaded trailer weight (per US Power Squadron, among others). If it's more, I would spend my efforts repositioning weight on the trailer slightly to reduce that weight a bit.

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'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

Fix the problem not the symptom; as Pete said tongue weight should be no more then 10% of the trailers weight.

Thats not much anyway, it should cause the car to sit like their is someone in the back seat.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I really wanted an airbag for the rear springs on the SDL to compensate for the loads in the trunk.

Looked around a bit until I also realized that the shock is inside the rear coils.

Guess who feels a bit sheepish for not having checked that out first..... I liked using air shocks on an old Caddy I had 'cause I could put in just enough air to have no effective change, By the time I load other stuff for 3 days in the trunk, the net effect is more than 90 lbs ....was hard on my Jetta (diesel)... Maybe I can slide the boat back a bit on the trailer -- for some reason, the wheels are pretty far back on it in relation to the center of the boat.

Thanks for the input.

Ed