TD transmission Info
 

I wanted a lower first gear to go with my high-speed rear end. The stock 300SD has 3.68. I looked through the archives and found out the 300TD has a lower first gear. I found reference to a 3.86 first gear. But I found one reference to a 4.25 in a wagon, which would be perfect. Does any one know how I can identify one of these transmissions? Maybe some confirmation on what the TD first gear ratio really is. RPM vs. MPH in first gear from some of you TD owners might help; I could do the calculations from that.
Thanks In advance.

Ok, can some one owning a 300td please tell me what rpm they are running in first gear and at what mph so I can calculate the first gear ratio.

This Polish website has a lot of good data on transmission gearing:

http://macmerc.netium.com.pl/index0.html

Drill down a level or two and I think you will find what you need - look for the spinning gears if you don't read Polish

I can't find the transmission data on that site. I found the technical data and even some wiring diagrams and the engine and chassis manual. The site has some neat information. Too bad I can't read polish. I even looked for one of those free translators.

I. 3,98; Ii. 2,39; Iii. 1,46; Iv. 1,0; R. 5,47

Belton - Think I have heard of that place

So there is no 4.25 first gear on a 722.315. I remember finding it in the archives. I even saved it to a text file.

gears
 

my diesel haynes shows no gear ratios. my haynes 77-81 2803 manual shows 3.98 early and 3.68 late models.

if anything had a lower first gear it would be a 240 td which would be a euro model of course... this is a guess. also on my 115 240 it seemed as if the first gear was very low geared. this might be an avenue as i believe some of those trannys would bolt in.... but for me it would not be a chore worth doing unless my tranny was shot and needed replacing.

TD owner....
 

I have a 300TD, I'm almost 100% sure the trans is the same. Mine is a 722.315, pretty sure most of them are, expect cali cars.

The way I read the data on the Polish website , for a 300TD after 9/81:

I. 4,25; II. 2,41; III. 1,49; IV. 1,0; R. 5,67

There's your 4.25 ,Frank

You are right! Wasn't very good at navigating the polish site :(

Thanks for the information. I really appreciate it. Is there any way to identify a 300td transmission?

I checked the EPC and the part number for the 82-85 tranny is the usual 722.315. So I don't know how you would tell them apart without the engine or car attached. That seems odd.

Is there another series of numbers after the 315 that could designate the different gear ratios like 722.315.xxx. I looked at my transmission, but it looks like mine has been rebuilt. The rebuilder took a grinder and wiped the part number off of mine.