Cost Comparison: Replacing Transmission vs. Converting to Manual
 

Just kind of curious at this point...I have a 1992 300D with 223,000 miles on the original tranny. Tranny works great but eventually the time will come when I will need to have it replaced. So I've wondered what would be involved, when the need arises, in converting to a manual.

My assumption is that I can get a reman tranny for about $2,000 including shipping, plus whatever the labor cost would be having it installed. What do you think the total cost would be to convert to a manual? And, aside from cost, what difficulties/pitfalls are associated with such a conversion?

Bottom line: I miss driving a manual.

I have "almost" everything you'd need to convert to a 5-speed setup sitting in my garage right now, including a recently rebuilt tranny. If you were converting a W201 (190 series car) to a 5-speed, I would have 100% of everything you'd need.

5-speed 190's are not too difficult to come by. 5-speed W124's (your 300D) are much more rare.

Working from memory, the only differences between installing a 5-speed in a W201 and a W124 will be:

1: Front driveshaft - you'll need a W124 5-speed front driveshaft, or a modified automatic shaft. You may need a new front flex disk, depending on which shaft you end up using.

2. Tranny crossmember - the W201 and W124 use different crossmembers. You may be able to modify an automatic crossmember (not sure, but it's possible on a W201)

3. Shifter rods - I'm not sure if the rods are the same length between a W201 and W124.

The items which are the same are as follows:

Tranny, flywheel, clutch, pressure plate, pilot bearing, throwout bearing, pedal cluster, shifter, master cylinder, slave cylinder.

You can typically buy a complete setup for a W201 for under $1000, then your additional costs would be the front driveshaft and possibly the shifter rods and a flex disk.

I hope this may be of some help.

SteveM.

I've done a few conversions to manual transmission, but cost was never a consideration or motivation. I did it because I LOVE manual transmissions.

If you can find what you need and do the work yourself, I would be SHOCKED if it didn't come in at less cost than rebuilding a Benz slush box.

I can't do the work myself. What I'm trying to compare is (a) having my tech replace the transmission with a reman that I can get for $2000; and (b) having my tech procure the necessary parts and do the conversion to a manual.

Cost benefit
 

Sometimes it is cheaper to get another used car with a working transmission and just drive it.

If you are in love with the car, then buy a parts car for $50 and swap yourself.

I converted a 1990 Saab 900S Automatic (with a burned out BorgWarner (junk) transmission) to a 5 speed manual. I paid $50 for each car and did the work myself in the driveway. My cost on parts etc plus a lift was about $600. I sold the parted out car parts for around $200 total.

Paying someone else to do the job was not an option for me.
Good luck

Yes, the parts car is the ONLY way to go and further more it's best if the donor (parts) car is within easy walking distance of the recipient. This is because to do a nice conversion there will be several tiny bits that you won't think of until you are in the throes of the project.

Even paying a tech to do the labor will result in nearly a wash.