Tech Support March 2009 - Rear End

Here's where we act like we know something technical about cars. Feel free to ask us about your technical troubles. Write us at tech@superstreetonline.com or Super Street c/o Tech Support, 6420 Wilshire Blvd., Los Angeles, CA 90048. Feel free to include a picture of your project or tech problem.

Question Of The Month
Q I own a 98 DC2 LS. That is not the problem. The problem is the automatic transmission. In first gear and second, occasionally it slips. Sometimes it shifts hard. I have flushed it out and put all new clean fluid back in, but got the same results. Is there something I didn't do right or do you think it's time for a new transmission? The previous owner put about 165k on the car, but it was clean when I bought it. Now sitting at about 185k, has this transmission just seen better days? Tell me something. Keep up the great work (for your minimal pay). I'll continue subscribing.
K.J.
Via the Internet

A Diagnosing a problem on an automatic transmission is difficult enough when you have the car in front of you and nearly impossible when you can't see or drive it. There are a few signs you should be looking for that could indicate an internal problem with the clutch packs. First, look at the condition of the fluid. If it's dark in color and smells burnt, chances are that it's time to rebuild/replace. The other thing is to check the bucket that you drained your fluid into to see if there are any metallic flakes or bits of clutch material deposited at the bottom. These are tell-tale signs of an internal problem. If the fluid looks good and the bottom of your bucket is clean, the next step is to check for transmission-related codes stored in the computer. It's possible to have a failure with the solenoid that controls the line pressure in the system, which can lead to a slip. On the other hand, if the codes hint toward a mechanical problem, the unit will likely need to be torn apart for an inspection.

Q Hey guys, you have the best magazine on the import scene and best advice so this is why I wrote you. I have a Nissan 240SX with a little over 200k miles on it. It started to overheat out of nowhere and I checked the usual. I changed thermostat, fan clutch (mechanical fan), flushed my system and checked my water pump but my car would still overheat. Now the kicker is that when it overheated a lot of white smoke came out of my exhaust, so I put in block seal just in case it was the head gasket. After that was done my car still overheated and still emitted white smoke. SoI thought to myself, maybe my thermostat is still bad. I changed it, then I took it out and now my car doesn't overheat. My question is, is it safe to run my car without a thermostat?
Michael Gomez
Via the Internet