700R4 going to sh*t. Need help.

[jdyates]

Today after school i noticed that my truck was shifting HARD, as if it was SLAMMING itself into gear. Then a little while later, it refused to shift from 1st at any RPM under 4500 (meaning i had to floor it to get it to shift). Took it to my buddy's dad, who is a respected mechanic, and he told me it might be due to a bunch of gunk contaminating the tranny fluid. He recommended running a small amount of brake fluid through to break some of it down, and it worked for awhile, truck shifted better than ever. But then on my way home from his house, it started shifting pretty late, at higher-than-normal RPM. My uncle then recommended i drain the tranny, replace the filter, put new fluid in, and reseal it with a new gasket.

Thoughts, anyone? Like what might be causing it, or if the filter/fluid change, will help?

 

[milky9788]

How many miles?...And what color is the fluid?

 

[Mean Green]

How many miles?...And what color is the fluid?

X2 on that. I would also advise you to drop the pan and check for filings and see what the fluid looks like, the color can tell you alot about whats going on. Do NOT flush the transmission at this point. Also, you might want to run some Lucas TransFix through it, anything Lucas makes is good stuff in my opinion.

 

[milky9788]

X2 on that. I would also advise you to drop the pan and check for filings and see what the fluid looks like, the color can tell you alot about whats going on. Do NOT flush the transmission at this point. Also, you might want to run some Lucas TransFix through it, anything Lucas makes is good stuff in my opinion.

I second the lucas and dropping the pan...Lucas is amazing.

 

[jdyates]

I've used Lucas fuel system cleaner, and i admit the brand is awesome, haven't tried the Trans stuff though. The tranny fluid itself is almost clear, kinda like a peachy looking color. Me and my dad are going to drop the pan on friday and get some new fluid in it. He recommended not to flush it as well, that some new fluid and trans conditioner will probably help.

Oh and I'm pretty sure my tranny is original, 199,*** miles. She has ran perfect until now. Truck has been a ranch truck its whole life, sitting on my uncles farm until he gave it to me. He also used it as his sheriffs vehicle way back in the day, just for city driving. AFAIK, it has never been run too hard or tore up.

 

[jdyates]

Okay, guys, here's the SitRep. Dropped the pan and drained the old fluid out, and found a TON of sludge or gunk or whatever at the bottom of the pan, so i cleaned all that crap out, got a new gasket and tranny filter, and put it all back together. Filled it with O'Reillys "premium" ATF and some TransEx stuff. Started her and drove her around the block. Seems to be sealed tight with no leaks (ill check periodically for the next week i suppose). She kept shifting hard and really late (around 2800 to 3000, not normal for mine) but after all the new fluid and Repair **** cycled through, she started driving normally, shifting all the way up to OD with no problems.

I'm curious, at what RPM do you guyses trucks shift from 1st to 2nd? Mine is at around 1800 now, when it used to be at around 1300 or so. Im thinking since i never changed the tranny fluid while ive on the truck, i got used to it shifting at the wrong RPM, and now it shifts at a good RPM? I'm going to work in a bit, ill see how she fares with more city driving.

 

[ndians68]

kinda sounds like a shift selinoid going bad (idk, i dont know anything about transmissions, just a guess)

 

[towman]

i think a 92 still has the tv cable adjusting the shift points, google how to adjust the tv cable, have seen some good write ups on how to adjust, if out of adjustment can burn up a trans real quick

 

[Mean Green]

i think a 92 still has the tv cable adjusting the shift points, google how to adjust the tv cable, have seen some good write ups on how to adjust, if out of adjustment can burn up a trans real quick

X2! Your shift points seem to be a little high, you should be shifting out of first before 1800 RPM's in a normal acceleration situation. TV cable adjustment, could very well remedy that problem! It's very simple, just do a quick google and I'm sure it should bring up several articles on how to do it if you are unfamiliar with it!

 

[jdyates]

Hmmm sounds like it could be a valid problem, but how would the tv cable "adjust" itself randomly like that? Remember, i drove it to school, she was running fine, then after school she went to ****. Me and dad swapped the fluid out and used trans conditioner and now she runs great, other than the shift points being at a slightly higher speed/rpm.