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Transmission won't shift into 3rd gear

13K views 16 replies 5 participants last post by  astro355 
#1 ·
I have 1997 Safari and it will not shift into 3rd gear. I have had the transmission replaced with a used transmission and the same thing is happening, it will not shift into 3rd gear. I have had the neutral/safety switch replaced and that has not done anything. My latest recommendation is to have the computer reset to see if that helps. Any ideas/suggestions would be appreciated.

Thanks!
 
#3 ·
Yes, reset the computer and let us know what happens next. The neutral safety switch only affects when you can start the van, which is only park and neutral. It prevents the van from being started while its in a forward or reverse gear.

Was there any other oddities that occurred with the original transmission? Or the van for that matter?
 
#4 ·
Hi ozzy19
Same problem with 2 different transmissions? Hmm, If the above advice doesn't cure it, then might I suggest you check the harness that leads to the transmission. I just made a post about this in another thread which is easy enough to check.
viewtopic.php?f=70&t=1528&start=10
The computer needs a clear signal to communicate on all wires that hook into the transmission. This particular plug-in gets a lot of abuse from dirt and moisture due to it's location (Drivers side rail). Hope this helps. Please keep us updated, Thanks.
 
#6 ·
Matrixx said:
Hi ozzy19
Same problem with 2 different transmissions? Hmm, If the above advice doesn't cure it, then might I suggest you check the harness that leads to the transmission. I just made a post about this in another thread which is easy enough to check.
viewtopic.php?f=70&t=1528&start=10
The computer needs a clear signal to communicate on all wires that hook into the transmission. This particular plug-in gets a lot of abuse from dirt and moisture due to it's location (Drivers side rail). Hope this helps. Please keep us updated, Thanks.
Yes, corrosion sucks. I would love to have a number of how much money was spent replacing parts that didn't need to be replaced just because there was corrosion in the connectors. Has the OP reest the computer yet?

And no, its not going to be the shifter linkage.
 
#7 ·
Thanks for all the feedback. I am currently at work and will be resetting the computer once I get home today, I will keep you all posted. One question I had about this plug/harness that goes from the computer to the transmission, can you replace this plug/harness?

Thanks again to everyone!
 
#8 ·
You could put you would be replacing the entire engine harness and they are very expense. Wires don't usually fail, unless they is obvious damage such as being pinched or overheated for extended periods of times. Problems related are at the connectors, where two pieces of metal touch. That's where you would find any corrosion.
 
#9 ·
There isn't any outside condition with the 4l60e trans that causes loss of third gear only. Are you sure it's third that you are missing?
Electrical problems can give you first gear only, first and fourth only, or second and third gears only.
 
#11 ·
I am sure that the tranmission was replaced and I'm sure that I have 1st and 2nd gear. It will not shift from 2nd gear to 3rd gear while in over drive. Furthermore, when I manually shift to third gear it does the same thing as it does when I am in overdrive. I guess the real question for me is if I try to reset the computer and it still doesn't shift from 2nd to 3rd gear, what woulb be the next step?
 
#12 ·
What gtkane means is that you maybe starting in 2nd gear and are never in 1st. I know, you would assume the gear that you start in is first but it could be starting in 2nd.

Hoes is your acceleration from a dead stop? A tach would be a great value right now.
 
#14 ·
Can you take a picture of the linkage to the trans (under the van)? Maybe you ran something over? I just it hard to believe that you would have two different transmissions that do the same thing when you are manually shifting them. Its possibly but not very likely.
 
#17 ·
Well, I hope you were unlucky enough to have two bad transmission and that replacing it again will solve the problem. Did you take it to the same shop that replaced the transmission the last time?
 
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