Strange Vibration...

Steven242 · Post by **Steven242** » 16 Feb 2009, 04:17

Well, here is the long story short...

Went to Tampa, drove fine.
On the way home, stopped for gas, noticed the vibration...
Checked all Fluids, Tranny was low, Dipstick was dry. Only needed a quart though.
Viration only happens at idle driving speed AFTER you give it a little gas and is in drive gear.

Symptoms... It only seems to happen in first gear right when it wants to go into second. Neutral, Reverse, and Park seem to have no signs of the mysterious vibration.

I stopped at Autozone last night, and picked up some Lucas Trans Fix. Stops slipping, stops hard shifts, conditions bands, equalizes line pressure and seals most leaks. I can be stopped at a stop sign/light, and it will idle smooth, I can pull it out of gear into N and give it a small rev and no shake. When I accelerate moderate to hard there is NO Vibration, and when I come to a stop from more than 40mph there is no vibe... ONLY when I am idling thru a parking lot and give it a little gas to get around a turn, or when I come to a stop below 40mph does it have a vibration.

I don't think it is an engine problem...
I am leaning towards a burnt friction band for second gear.

Since I may have burnt up my trans, can someone give me the alphanumeric code for the four speed auto no overdrive for a '78 Volvo 240?

Post by **billofdurham** » 16 Feb 2009, 11:27

These were fitted with either the Borg & Warner BW55 or the Aisin-Warner AW55 both of which were 3 speed boxes. I can find no record of the 242 being fitted with a 4 speed auto box.

Before chasing after a replacement box have you considered changing the fluid to see if it helps to overcome the vibration?

Bill.

Steven242 · Post by **Steven242** » 17 Feb 2009, 04:02

I'm going to be doing a Drain and Fill with a filter change when I get the chance later this week.

The vibration has almost completely disappeared with the addition of the Lucas Trans Fix.

I swear this box is a four speed. I feel it shift three times when in drive, which tells me four forward gears, and one reverse gear.

Maybe it is a north american thing with a four speed auto...

Post by **billofdurham** » 17 Feb 2009, 11:47

I swear this box is a four speed. I feel it shift three times when in drive, which tells me four forward gears, and one reverse gear.

Maybe it is a north american thing with a four speed auto...

The information I quoted relates to the North American model. What is at the side of the gear shift? If it is P; R; N; D; 2; 1 you have a three speed box. However, two possibilities come to mind:
1. Someone has put in a later 4 speed box. Highly unlikely as the most obvious choice would be the AW70 or AW71 both of which have the 4th gear as an overdrive so you would have a button on the stick.
2. It may, and I stress may as I am not certain, have a lock up torque converter which does give the impression that another gear has been selected. The lock up torque converter was used in Borg & Warner boxes in the 1950s but went out of fashion and only re-appeared in the late 1970s. I'm not sure when they appeared on the 240s but I do know they are on the AW70 and AW71.

Keep us informed about the drain and fill.

Bill.

Steven242 · Post by **Steven242** » 18 Feb 2009, 04:21

Well, haven't gotten the time to get the thing checked out and a drain and fill... but with the addition of the lucas trans fix my vibration has disappeared. I'm not going to be putting the procedure off just because of this, but at least it is helping me out. I've been working 14hr days last couple of days, and by time I get home it is 10pm. hopefully today I get off a little earlier to get it to aamco or another trans shop.

about the three speed or four speed box. My old '87 chevy S10 had a lock up torque converter in its 700r4, but it only felt like it had the four gears. Maybe I'm just new to this volvo stuff. I've always owned gm before, and my first non gm car and I am having a hard time understanding the components.