transmission slip from 3rd to drive...ugh

joshuachrist · #1 03-09-2010, 04:00 PM

I will try to do my best with the description of the problem. First, I have been reading past posts about similar problems. I have tried disconnection the terminal behind the battery with no help. When accelerating all gears are fine until it shifts from 3rd to 4th. When shifting between the two gears I can feel a harsh slip(revs jump up). Thus I have to steady the rpm's and gradually accelerate. This is a huge problem when trying to get up to highway speed. The problem has been going on for about a week now...before it started i noticed a noise coming from the tranny so I took it to the garage. They told me that i had a leak and and replaced the fluids/filter. Everything was fine after that for a few weeks. Now i notice the slipping. On a side note; is there an overdrive on the SVX? Ever since I've owned it it would shift into 4th...then after a little shift again like it was going into an overdrive. I mention this because once i reach highway speed after all the slipping and get into this "overdrive" everything is fine. Im sorry if my post is unclear but any help would be greatly received. Thanks

Blacky · #2 03-09-2010, 04:48 PM

Two things come to mind; brake band adjustment on the transmission and/or TPS (throttle position sensor).
Here's a link for the brake band: http://www.subaru-svx.net/photos/files/How-To/34159.pdf

Here's the TPS: http://www.subaru-svx.net/photos/files/How-To/14293.pdf

I don't mean to be pessimistic but your tranny could be on it's way out also.

joshuachrist · #3 03-09-2010, 04:51 PM

Quote:

Originally Posted by Blacky

I don't mean to be pessimistic but your tranny could be on it's way out also.

yeah, i'm already pessimistic. that's why i'm trying to stay hopeful and come here to find some expert advice

trophy956 · #4 03-09-2010, 05:26 PM

hi your high clutch is slipping ,SVX 4eats had a lack of oil ,to this clutch
they redesigned the hub and made the bearing smaller trying to stop this ,it wasnt really fixed till the 98 model year ,and the brake band is 2nd and 4th
tps doesnt cause slipping but would make erratic shiftes
charlie

joshuachrist · #5 03-09-2010, 05:37 PM

Quote:

Originally Posted by trophy956

hi your high clutch is slipping ,SVX 4eats had a lack of oil ,to this clutch
they redesigned the hub and made the bearing smaller trying to stop this ,it wasnt really fixed till the 98 model year ,and the brake band is 2nd and 4th
tps doesnt cause slipping but would make erratic shiftes
charlie

so what are my options? rebuild or get new?

1986nate · #6 03-09-2010, 05:45 PM

Quote:

Originally Posted by joshuachrist

so what are my options? rebuild or get new?

Contact svxfiles "old tom". He is about 3 hours from you in Wiley Ford, WV. He can set you up with 4.44 gears which have been proven to hold up and last on the SVX. He's a great guy and I'm sure he'll be glad to help you out.

joshuachrist · #7 03-09-2010, 05:54 PM

Quote:

Originally Posted by 1986nate

Contact svxfiles "old tom". He is about 3 hours from you in Wiley Ford, WV. He can set you up with 4.44 gears which have been proven to hold up and last on the SVX. He's a great guy and I'm sure he'll be glad to help you out.

that works considering i go to charleston wv all the time for work.

Blacky · #8 03-09-2010, 08:26 PM

Quote:

Originally Posted by trophy956

tps doesnt cause slipping but would make erratic shiftes
charlie

Actually my recently 4.44 swapped Claret was doing a pretty good impression of slipping (hesitation and revving up) from 2nd to 3rd and by adjusting the TPS I totally eliminated it. I knew the tranny was perfect so it had to be something else.

NiftySVX · #9 03-09-2010, 09:30 PM

The TPS is unlikely to cause this issue. It isn't the TPS, but you can check it if you like.

I would suggest that you have the unit rebuilt and the valve body modified. As mentioned earlier in the thread there was a change to the high clutch drum and related components to improve durability, which you will want to be sure is included in your rebuild. Also, a valve body modification will get the problem at the source and will be the best possible chance you have at avoiding a repeat failure as the fault lies with tuning of the hydraulics in the body.

You may be interested to know that my diagnosis is that your vehicle is showing symptoms of a burnt brake band which is a direct cause of either lubrication breakdown or insufficient pressure being applied to the band servo to hold the drum stationary. The high clutch is not necessarily slipping, but this is insignificant because I can promise you it is in need of work even if you don't notice any symptoms. Having said that, it doesn't really matter wether the band is causing the problem or the high clutch, because they are both trash at this point.

The change to a different gear ratio is your choice, but if you'd like to maintain the sedate, quiet cruiser characteristics of the SVX I would stay with the 3.545 ratio.

joshuachrist · #10 03-10-2010, 12:59 PM

thanks for all the help, im pretty broke right now and my 1.8t beetle just crapped out on me(again). Luckily my bike is running. i dont know what im going to do just yet but ill try to keep everyone posted.