I replaced the auto trans in my car and while doing the swap I found that my last repair on the OD solenoid using the flexible corrugated wire wrap looked like a mess.

The corrugated plastic wrap had melted to the top of the transmission.

The wiring wasn't damaged but I'm wondering if it is necessary to run the wiring the way Volvo meant for it to be run. It originally comes out of the floor then over the transmission to the passenger side of the trans and then back over to the drivers side of the trans to the solenoid.
I'm wondering if anyone has perfected a new way to run the wiring using some other type of flexible wrap that won't melt to the trans.

I seem to remember that the original wiring wrap had melted in a similar way.

Can I just drop the wiring down on the drivers side and put it through the hold down that is right in front of the solenoid?


Any help is greatly appreciated.

Go to the parts store and buy a piece of 3/8" high temp hose. Run the solenoid wire through it and ty wrap or tape the ends shut. You should not have any problems with heat after that. If you do not drive the car around in third gear all of the time, you might consider modifying the solenoid so that the trans is a full time 4 speed and be done with it. There are several posts on the bulletin board that detail this procedure. I am using on my 240 DL that is used in a 100+ mile daily commute and it works great!

I have not seen a transmission get hot enough to melt the plastic wire wrap unless there was an internal problem or cooler blockage. Got any unusual noises coming out of it?

If you route the solenoid wire down the driver's side, there is a possibility of getting caught up in the shift linkage.

Best of Luck,

Big Harry

I replaced my transmission because it wouldn't go into fourth gear.
The solenoid had already been modified before I got the car so it would always go to fourth but then it slowly stopped going to fourth until it finally didn't. I then replaced the solenoid and ran new wiring but it never went to fourth again.
The plastic wire conduit might have melted to the trans because it was always in third gear and so it was getting hotter than normal.
When I replaced the trans with a lower mileage unit, I used the same solenoid and wiring but the wire routing seems a little extreme.
The heat resistant tubing sounds like a good idea.
I'll have to see what the parts store has.

Thanks.
Kyle245

Having been in the plastics industry for a number of years, I would say that the tranny is too hot. Even low grade plastics have a melt temperature of around 300F. The only way for it to get that hot would be slippage or a bearing failure. This would increase the temp beyond the cooler capacity.

If the tranny quit shifting into fourth gear, the spool that shifts it either wore out or stuck. I still like bypassing the solenoid.

Big Harry