A few questions about a 98 V70 AWD

bronco · Post by **bronco** » 11 Aug 2019, 19:58

So this is my first post on the site , I just joined today , I've known about the site awhile , it pops up in searches at times and I've been helped by reading others questions and answers on different subjects. I've owned a 1994 940 , and a 2001 S80 , and a 2000 s70 at various times in my life and like the brand a lot. I'm on my 4th volvo now a 98 V70 .

So I've been driving a 1998 volvo V70 AWD as a second car for about a year now . I basically use it to get around outside of work hours when I'd be driving a pickup truck.

I got a good deal on it but it had a few issues , some dings in the body work , oil leaks which the previous owner couldn't fix and the fact that the rear driveshaft had been removed for some reason.

Because it was only local driving I just ignored the driveshaft , I didn't care about AWD and everything seemed to be ok as a FWD.

The oil leaks were the turbo supply line and the o ring on the return tube and while annoying because of the angle gear were solved early on , I just bit the bullet and took the turbo and all that stuff off and swapped parts from a donor or two to get everything straightened out.

Long story short I like driving the car and decided to take it camping and discovered a few issues on a long distance highway trip.

The transmission shifts a little funny after a few hours on the highway , the fluid was a little brown so I did the flush procedure I found on this site I'm hoping that will improve the shifting as the fluid was a little burnt. I'll need another long trip to tell as it never does anything odd in short trips

The other thing is the rear diff makes noise at high speed . I have no intention of ever putting the rear driveshaft in , but the rear axle shafts are still in the car so they are , I assume , spinning the diff at road speed.

So two questions , can I just yank the rear shafts out and throw them away? Without changing to a bearing setup for a FWD car ? I have donor parts from FWD 's of the same year but it seems like the wheel bearings should work fine without any axle shafts going through the middle , and without the shafts the diff can't spin and make noise or cause any mileage loss from drag.

I have a pair of S70 parts cars in the yard , if the tranny blows up can I swap in a FWD transaxle so I don't need to deal with the annoying angle gear all the time? Alternately can I swap in a 5 spd transaxle from a FWD car instead if I found an s70 donor with a standard? I'd always rather have a standard if possible , I have ford trucks with standard transmissions with over 300,000 trouble free miles it seems like it would be an upgrade plus obviously more fun to drive if I could put in a 5 speed.

A third unrelated question , what is with the utterly stupid muffler setup on this thing? The pipe goes into a muffler on the drivers side with no tailpipe outlet then over to a muffler on the passenger side. I can't imagine a less efficient design , what were they thinking?

There is no emission testing here after 15 years so I don't need to keep a stock appearance. Is there any reason not to cut the right and left mufflers off and put a turbo muffler on the left with an outlet?

Any input would be appreciated , links to other threads , I did search but didn't turn up anything specific to the diff issue thats most pressing.

Post by **RickHaleParker** » 12 Aug 2019, 01:01

bronco wrote: ↑11 Aug 2019, 19:58 A third unrelated question , what is with the utterly stupid muffler setup on this thing? The pipe goes into a muffler on the drivers side with no tailpipe outlet then over to a muffler on the passenger side. I can't imagine a less efficient design , what were they thinking?

The first one is the Resonator. The second one is the Muffler.

callahanoffroad · Post by **callahanoffroad** » 12 Aug 2019, 05:46

Hi!
Welcome to MVS, you'll love it here!

Let me first answer your questions by saying with the P80 platform, anything is possible and almost everything is interchangeable with a few specific exceptions. Some things are more complicated like swapping a turbo motor into a non turbo car. Some things are completely uncomplicated like using a 99 fan in a 93. Just plug and play.

RPH already answered the exhaust question. But I'll add that if you wanted a custom 3" turbo back exhaust they do exist. Or you could fabricate your own if you're so inclined. Unless you deleted you cat a custom exhaust shouldn't have anything to do with emissions.

As far as manual swaps go as long as you have a donor car you're good to go. There are many many many write ups on how to do it, and I think there are some in the repair database here on MVS. Usually they tell you every last piece that you need before you even start.

If you want to permanently do away with the AWD IIRC you'll need to completely remove the entire rear suspension setup and replace it with a FWD setup. From what I remember they are very different. You'd also want to swap transmissions to clear the space in the engine bay. But someone else will chime in. You should also be able to search for that here on MVS.

bronco · Post by **bronco** » 12 Aug 2019, 19:57

RickHaleParker wrote: ↑12 Aug 2019, 01:01
bronco wrote: ↑11 Aug 2019, 19:58 A third unrelated question , what is with the utterly stupid muffler setup on this thing? The pipe goes into a muffler on the drivers side with no tailpipe outlet then over to a muffler on the passenger side. I can't imagine a less efficient design , what were they thinking?
The first one is the Resonator. The second one is the Muffler.

The Sedans don't use the same setup it seems like , is it maybe because the larger internal volume of the wagons makes the sort of exhaust they use in the sedan too loud?

I'm not opposed to a louder exhaust I could just cut the pipe as it enters the resonator and drive around with nothing back there and see what I think of it. Later I could slap just an aftermarket turbo muffler on the left if its too loud.

Another random question , where are folks sourcing replacement vacuum tees and lines caps etc ? I have some crumbly hoses to replace , my donor vehicles are no help with that they have hoses that look even worse.

Post by **abscate** » 12 Aug 2019, 20:51

You might be out of range of emissions testing but removing a cat is illegal in MA. Check your inspection station before you dive in.

Post by **RickHaleParker** » 12 Aug 2019, 21:17

abscate wrote: ↑12 Aug 2019, 20:51 You might be out of range of emissions testing but removing a cat is illegal in MA. Check your inspection station before you dive in.

Removing a catalytic converter is illegal under federal law.

"Under federal law, catalytic converters may not be removed and replaced with "converter replacement pipes' by any person. The 1990 Clean Air Act Amendments even prohibit private individuals from installing "converter replacement pipes" on their own vehicles. Anyone who installs such pipes would violate section 203(a)(3)(A) and (B) of the Clean Air Act (Act).

The only circumstances in which a person would be allowed to remove a converter is if the vehicle is being shipped overseas to an area where unleaded gasoline is not generally available. (Vehicles traveling to Canada or Mexico are nnf; eligible for this exemption.) In this instance the vehicle owner must have a letter from the EPA specifically authorizing the converter removal from the vehicle in question. "

* Source: United States Environmental Protection Agency.

Post by **erikv11** » 12 Aug 2019, 22:05

bronco wrote: ↑12 Aug 2019, 19:57 ... Another random question , where are folks sourcing replacement vacuum tees and lines caps etc ? I have some crumbly hoses to replace , my donor vehicles are no help with that they have hoses that look even worse.

My recommendation is to just get generic rubber vacuum line, or generic silicone vacuum line. Replace them all. Better to not mess with the plastic hard lines etc, get enough line to connect point A to point B without them. I prefer silicone but rubber is cheaper and works well.

This post should help you sort out all the lines: viewtopic.php?t=63615

bronco · Post by **bronco** » 13 Aug 2019, 07:16

abscate wrote: ↑12 Aug 2019, 20:51 You might be out of range of emissions testing but removing a cat is illegal in MA. Check your inspection station before you dive in.

Well there is nothing wrong with the cat itself . I meant cutting the pipe behind the rear axle as it enters the resonator. In effect using just a cat with 8 feet of straight pipe behind it. If it sounds awful I can put a simple $20 turbo muffler right at the end on the drivers side and have it exit right at the bumper. The right rear hanger is broken and the exhaust moves around a bit, if I don't replace the hanger then another hanger is probably going to go soon That exhaust is damn heavy it needs as many hangers as you can put on it. But , it only clunked a little when you put it in reverse from park once in awhile so I never looked at it . I always assumed it was a sloppy motor or tranny mount making that clunk. When I fixed up the turbo I replaced the missing bolt in the upper mount and checked the others and realized they were not the source of the noise. Whats up with volvo having that bolt point down?

When I first started messing with the oil leaks I found it pinched between the exhaust and a part of the frame and had no idea what it was doing there or where it was from. When I put a bolt in the firewall I trimmed a little plastic from the wiper area and had the head of the bolt pointing up instead of down like it should have been from the factory.

Thats the thing with the rear diff, I thought it would be disabled with the rear driveshaft out and until I got out on the highway for a long way I never heard a sound from it. With the axle shafts in though , the guts of it must be spinning at road speed all the time, its probably dry inside and there is a bearing making the noise. My normal MO would be to wait for a rear wheel bearing to go bad then take out that half shaft and install the bearing on that side without a shaft then stop thinking about it until the other side went. That would still leave the diff spinning and it might not be the side with the noisy bearing. However , pulling both shafts seems like it would stop all the noise and be cost free other than a few hours and maybe some acetylene . I'd probably save a little gas from the reduced drag going forward though.

greg850r · Post by **greg850r** » 21 Aug 2019, 20:33

bronco wrote: ↑13 Aug 2019, 07:16
Thats the thing with the rear diff, I thought it would be disabled with the rear driveshaft out and until I got out on the highway for a long way I never heard a sound from it. With the axle shafts in though , the guts of it must be spinning at road speed all the time, its probably dry inside and there is a bearing making the noise. My normal MO would be to wait for a rear wheel bearing to go bad then take out that half shaft and install the bearing on that side without a shaft then stop thinking about it until the other side went. That would still leave the diff spinning and it might not be the side with the noisy bearing. However , pulling both shafts seems like it would stop all the noise and be cost free other than a few hours and maybe some acetylene . I'd probably save a little gas from the reduced drag going forward though.

I would just put some oil it it and worry about it if that didn't help