Hello all, hoping any of you guys here could answer a question i got
Does the m58 transmission off of a 850 awd have a different sub frame than the non awd 850's
What I am doing is manual swapping my 97 850 sedan with the m58.
Already know that ill have to make a plate to cover the angle gear. Just would like to know if i have to swap the sub frame.

Thanks!

 

Just updating this post for future reference for guys crazy enough to want to do what im attempting to do.

Basically yes you can use a m58 from a awd and put it into a fwd for a manual swap without swapping the subframe.
Some modifications must be done to the transmission case itself for it to fit correctly.
The fwd cars have a rear mount that bolts onto 3 holes on the transmission itself
The awd cars have a driver side mount much like the passenger side motor mount found on both awd and fwd
The fwd mount wont work without some machining
To get around this you must remove some webbing and take the boss down marked in red to allow the fwd style trans mount
Luckily volvo decided for whatever reason to have a casting that allows you to modify the transmission to still use the fwd mount.
you need to drill and tap 3 holes marked in green. these holes are all on different steps some higher some lower.
Essentially to do this job you need a milling machine large enough for this work
I will post pictures when I finish making the mod to the casing hopefully tomorrow

 

Well, thanks for posting! I've never even seen an AWD down here in the USA, so I don't suppose I'll ever be doing that. I'll bet the later automatics we got have the same differences.

 

No surprise you dont see them down there. They were only imported to canada in small numbers, (around 300 to canada, and about 3k made overall) so fairly rare but this example I tore apart has seen better days and was nearly unfit for even a winter beater for a season. poor paint, bad rust, and a worn engine with rtv silicone for a head gasket! So i dont feel so bad about parting it

 

Been longer than "tomorrow" but heres a update all the same
Got a few photos here showing what i did to the t case Basically what I outlined in a previous post, just cut the bits that interfere and tap the holes that should be there thats about it
Of course i took measurements from the auto case for the hole z axis (the 3 holes are on 3 steps) and took a feeler gauge to see the variance for each hole (bolt one hole and feel the other 2 with shims and do the same for the other 2 and you get a average +/- tolerance, which turned to be fairly loose about 5 thou.
Drilling the holes is easy for location, basically locate the pre drilled top hole and tap it and bolt the support on and with a drill that fits the casting hole snug line it up (the position is pretty loose here they are just bolt holes after all)
Next after that was done is to make sure she doesnt puke oil when you hit the road
The m58 has this splined collar that mates from the outboard pass side axle to the angle gear, of course im not using that so That hole needs to be filled, The splined collar is still used but its a semi loose fit, you need some force to push it into the seal but at 100km/h that spins at about 800rpm which will come loose and rattle on your axle
So i needed a way to retain that in the seal

I welded a cap for the spline that has a recess cut into it for a 27mm axle seal (the splines on the axle are 28 but the actual axle is 27) then coated the internal splines of the collar with sealant and installed it into the transmission, after that the retainer ring that clamps on the axle is installed which uses 4 screws to clamp on the axle (decided to add some high temp epoxy to make sure it doesnt come off)
and between those 2 is a thick brass washer. hindsight probably didnt need it but the idea was i didnt want the retainer ring grinding on the collar. so the brass washer would spin with either or if there was friction. not sure if i explained it well

And thats the mod done, did about 2000 miles 2 days after the swap and mods to portland and around BC. so far no leaks so i guess thats a good sign.The 5 speed is a huge improvement over the auto trans the 850s had.







One hell of a project but glad to have it done and working finally. Thanks for taking a look at my Frankenstein project!

 

Interesting mods!