Expert: Roland Finston - 10/27/2011

Question
QUESTION: I have a 1993 LeBaron LE 3.0 six w/3 speed tranny about 110,000 miles, which for the last year or two, has slowly been shifting at higher and higher speeds. This spring I had tranny fluid and filter changed because it was periodically shifting into 2nd at about 24 mph and 3rd at about 40. Seemed to be worse on colder days. No immediate change, actually seemed to get worse. Changed distance speed sensor no immediate change. Now it shifts into 2nd at about 28 mph and 3rd about 50-55. Downshifts 3-2 at about 40 and 2-1 at 10-15mph. Any ideas?

ANSWER: Hi Mark,
I want to ask for one clarification: is this transmission a non-electronic 3-speed or an electronic 4-speed? I had the impression that the 3-speed was only used with the 4 cylinder engines and the 4-speed was with the V-6. If it is indeed the 3-speed then the one adjustment that may need to be made is the throttle pressure cable and rod as that being 'out' can affect the shift points. Otherwise, I haven't seen any other possible causes for your problem. Let me know and I can share a page about this by xerox copy and postal mail.
Roland

---------- FOLLOW-UP ----------

QUESTION: It's a 3 speed. I believe it's a A-670 model tranny. The number cast into the housing is 426E.
The speed sensor I have is in the top picture.
http://autorepair.about.com/library/faqs/bl214i.htm
I do not have the input / output sensors that are in the bottom picture.

I don't know if this helps but some history. There is a hill when I drive east that flattens out at the top. Originally I would get to 40 mpg and it would climb the hill no problem in third. Eventually the tranny started to downshift but would go back to third at the top. Last fall I noticed that it wouldn't upshift at the top of the hill until I took my foot off the accelerator. Now it doesn't upshift until I reach 50-55.

Answer
Hi Mark,
I would try the throttle pressure cable adjustment. Do you have that text? If not, send me a follow-up question wherein you tell me your postal mailing address. I will copy the page and postal mail it to you. I don't know of any other reason for what you have there, other than to check the internal fluid pressures at the various ports. There is no specific fault description that is like what you describe.
Roland
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