All this started as a hard shifting gearbox, noisy in first/rev/and third. While changing the gear-oil on my 73/145, I pulled the "mag" plug and found about an inch of accumulated metal shavings holding onto the plug. I took the plug and washed it over a clean coffee filter. Finding only small sliver-shavings of steel (nothing large like gear teeth). Second, less than half a quart of oil drained out total. I pumped a quart of oil through the fill plug to see if I would get more shavings->more came out->a lot more. Should I be looking for a new gearbox? I re-installed the mag plug and filled it to service level. //// Next subject --> what option do I have to change the final drive ratio? Right now the car is completely stock, 4-speed (m40 I believe), no overdrive, 4.? ratio in the rear. All I know for sure is that freeway speed (65) tacks over 4000 rpm’s (closer to 5K). With most states (like Washington) going to 70mph freeway speed limits, The 145 stock was not geared to sustain these speeds with any sort of efficiency. If possible, I don't want to have my speedo re-calibrated. Any advice would help.---Eric--Portland, Or-

Sounds like the old self machining transmission to me. Good luck.

Sort of bad news there - brass shavings from the synchros would be understandable. At this point, maybe flush it out again and just run it until it fails. Are the bearings noisy? They may be soon.

Unless they changed a lot for the '73's, the Wagon came with 4.3:1 rear end WITH THE STANDARD, and 4.1:1 with the automatics. So, you could find a 4.1:1 fairly easy. Most folks opt for the overdrive tranny for better (quieter) distance-running. You could solve two concerns at once by fitting an overdrive transmission.
--
142E, 145S

Thanks for the advise,
I believe I am now looking for a M410 gearbox. Yes, my M40 does make a lot of noise. Being that my 145 is driven every day, I will use this gearbox untill I have a replacement ready to install. I will see what I can find at IPD on May18.
---Eric R.--145/73-Portland,Or.

You want an M41 gearbox. The M410 is the overdrive unit
on the 164 and 10-20 1970 1800s. It is unlikley that you
will locate an M410 that will fit your car, and if you do
you can trade it to a racer for an M41 + another volvo.
Plus the M410s tend to eat bearings.

The M41 that you're after can be found in almost any
1800 and many of the later 140s and the 1975 240. It is
easy to identify -- when you see one of these beasts in a
salvage yard, look to see if it's got the manual, then
look under and see if the transmission has a big aluminum
thingy hanging off the back of it. If yes and yes, then
pull it out. They're pretty common.
chris