I recently purchased a 1990 740 Volvo for my son. It needs minor work or so I suspect. Here is the major problem that I am facing at the moment. On initial start up the transmission (automatic) has to warm up before it will shift into the other gears. So I am driving around in 1st gear for about 5-10 minutes before it will go into 2nd, 3rd and 4th. Once it has warmed up it behaves like any other automatic, shifting very smoothly and pulling like it should. I have checked the transmission fluid and it is at capacity, but it is more brown than red. I am curious to know if changing the filtering screen will fix the problem I am having with this car? Or is there something additional I must do?

 

If all else were well with the tranny, I would say it is the modulator valve, but with the brown fluid, I would definitely have it changed along with the filter. You may see an immediate change.

 

Replace fluid and filter Fluid is probbably worn out. Heck that is the best place to start. And will give you a starting point in case nothing changes.

 

Some trannies are actually designed that way and the upper gears are locked out until it warms up. Can't remember makes/models (or how it is accomplished - presumably a temp sensor in the tranny), but I have heard of it. I don't think it's suppose to affect the shifting for more than a few minutes, tho.

Might also simply have a solenoid hanging up and the fluid change will fix it.

 

Thanks for all the replies, it seens that changing my tranny filter/screen is the 1st thing I should do (this weekend). Tow_Guy can you tell me whether this sensor is mounted internally or externally to the transmission?

Again thanks to everyone and i will let you know how it turns out saturday afternoon

 

No. Out of my realm of expertise and I don't even know if yours is so designed. Also, I think the ones that are designed that way give you more than just one gear. Typically they give you all but high gear.

 

That is where I would start. A new filter kit (if applicable as some auto trans filters are not serviceable) and most importantly use the factory recommended fluid. If you remove the transmission pan pay close attention to the sediment on the bottom of the pan. A brown silt like sludge would be normal on a high mileage trans that hasn't been serviced regularly. If this is all you find then a trans service may solve the problem. A lot of metal flake or chunks of debris may indicate something more serious.

I would avoid having the trans flushed with a machine as this tends to disturb and dislodge debris that can plug the fluid passages. A regular trans service now and then another in 5 or 10k miles is a better approach to cleaning the insides of an auto trans.

 

Well I replace me tranny fluid and screen this weekend. The car drove much better. The first time out it shift from 1st to second in less that 1/2 mile, today it shifted in less than 50 yards. It was a real shocking experience when I first release the old fluid it was a brownish-red and really really thick. Matter of fact after removing the pan. I assumed all the fluid had drained out boy was I surprised that when I removed the screen more drained out. Well everything is slowly working well now.

I am however having one issue the owners manual specifies that the tranny case capacity will hold 7.9 U.S quarts of ATF Dexron IID. Well from what I observed it will only hold ~4 quarts.

 

4 quarts is probably the amount in the torque converter.
It may not have gotten changed.

 

That is probably correct and why I would recommend another fluid change in 3k to 5k miles. Also Ames63 should make sure he is checking the level under the proper conditions which is most likely with the engine fully warmed up and running, transmission in park, and the car on a level surface.

 

Did you change the fluid yourself? You can do one step better and change ALL the fluid. It is done by using the "cooler line" method. You can search the internet or I can post the procedure. Basically, you break into the transmission cooler line, turn the engine on and pump out some of the fluid, refill the transmission, and repeat until clean fluid comes out.

 

I am very interested in completely flushing the entire system can you post the method for a complete flush?

I had no idea that it was not a complete flush. I guess my next question is will the new trans fluid completely flush out the old gunk over time? Also should I expect any quirts in performance by force flushing the tranny?

again thanks for everyones input, this has been very informative!

 

Ames, here it is in excruciating detail. This is the fluid change method I use on all my cars that don't have a torque converter drain:

Transmission Fluid Exchange

1. Pull the transmission dipstick. Fresh fluid is translucent and cherry red. Some darkening is normal, but if it is reddish brown or mustard color and smells like burnt varnish, it is worn out.

2. Make sure the fluid is warm.

3. Remove all pan bolts except for the corners. Remove the bolt from the lowest corner, then loosen the other corner bolts a turn or two. Carefully pry the pan to break the gasket seal at the lowest corner. Drain mostly from this corner. With good technique you can avoid or at least minimize the red bath.

4. Remove pan. Inspect the pan before cleaning. A small amount of fine grey clutch dust is normal. However, if you find metal shavings, there has been transmission damage. Remove all old gasket material. Some rubber gaskets are reusable. Clean the pan and magnet with solvent and wipe dry so there is no harmful residue. Shop air can be used to clean the magnet. Hammer back any pan damage from previous overtightening.

5. (Optional) Drill hole in pan at low point and install a drain kit available from most auto supply houses. Make sure the kit protruding inside the pan doesn't interfere with anything on the transmission.

6. Replace filter.

7. Position gasket on pan. Some gaskets have four holes slightly smaller than the rest to allow four bolts through the pan and through these smaller holes to hold the four bolts and gasket in place.

8. Hand tighten pan bolts in a criss-cross pattern. After that, use a torque wrench to tighten bolts to proper ft-lbs as per manufacturer.

9. Refill the transmission using only the amount shown as “refill capacity” in the owners manual (or an equal amount that was drained), using the type of fluid specified for the vehicle.

10. You now have replaced the trans fluid and filter according to manufacturer’s requirements. Fluid is changed in the pan only.

You can stop here and go to Step 17 if you just wanted a regular drop-the-pan fluid change. For a complete exchange of the fluid (including transmission body and torque converter) continue with the next steps.

11. Obtain the total system capacity of the vehicle from the manufacturer. Have this amount - plus a bit more - of fluid readily available.

12. Disconnect the oil cooler line from the oil cooler. Tickle the ignition to find the flow direction. Direct the stream of fluid toward a receptacle. It is better to use a clear length of hose with a shoplight laying next to it so you can see when all the old fluid has left the system.

13. Start the engine, let it idle to pump out old trans fluid until you start seeing air bubbles.

14. Stop the engine. Refill transmission through fill tube with fresh fluid - same amount as pumped out (usually about 2-3 quarts).

15. When either the fluid color brightens or the total capacity has been replaced, shut the engine off and re-attach the oil cooler line. All trans fluid has now been changed.

16. Button everything back up. Clean up the mess.

17. Recheck the fluid level. With the car on level ground, set the parking brake and the transmission in Park or Neutral. Let the engine idle for a few minutes. Shift the transmission through all detents, pausing momentarily at each position, before returning the lever to Park or Neutral. Check the fluid level again and check for leaks. Refill fluid so it is slightly undercharged. This way it can be properly checked and topped off after a long drive.

 

I would try Kestas method before I would have it flushed with a machine. His method is less likely to disturb a lot of gunk buildup in the valve body. ATF as a lot of detergent in it and with a few changes over time will clean out most sediment buildup.