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'14 Chevy Silverado Owner
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ok i have a 98 Chevy Silverado 1500 4x4 Z71 with the 5.7L 350 and 4L60E Auto Trans

problem is, sometimes it will shift hard, the worst is from 1st to 2nd, and each gear its not as bad as the last shift, but around town its perfect, it will only shift hard if i drive nonstop for maybe 15 minutes or more so mostly after driving on the highway, interestate or country roads

now it doesn't do it all the time maybe every other time at the most, but if it start to do it all i have to do is pull over somewhere and cut the truck off for a couple minutes, then i crank it back up and it shifts perfect and couldn't be anymore smooth of a shift, so thats making me think its a sensor since when i cut the truck off and cut it back on is resetting it

i took it to Autozone last year (ya its been doing it for at least 2-3 years i just cut the truck off everytime it happens) the codes came up (can't remember and don't have the print out anymore) but i remember the solutions would be, crankshaft position sensor, camshaft position sensor, off timing, knock sensor and change the transmission fluid and filter, it might be a couple more but can't remember now since i can cut the truck off and back on and the problem stops completly i figure it should have to do with a sensor, i probably should replace the fluid and filter but don't have the money

so far i've replaced the crankshaft position sensor and the distributor which has the camshaft position sensor in it, so it has a new crankshaft sensor and distributor which i also had a new camshaft sensor in it so i didn't reuse the old sensor

so what other options is left other than the knock sensor and maybe changing the fluid and filter, now i don't have the money to fix it right now or at least take it to a mechanic, im just trying to get an idea of what else might be the problem, i might try the knock sensor though if it doesn't cost to much
 

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The real reason for the problem is the valvebody - it needs to be corrected (and if done early enough in the life of the tranny - it won't cause damage). The real culprit is the TCC regulator valve. You NEED to replace the regulator with a Sonnax TCC Valve Regulator Valve Kit found here http://www.transmissioncenter.net/PinHole.htm quarter of the way down - after #43G.

There are two different Sonnax kits:

Sonnax #77754-03K - 93-97 (except EC3) - 4L60E (roughly $40)
Sonnax #77754-04K - 98+ including EC3 - 4L60E (roughly $40)


To do this repair correctly - you need to find a shop that has the correct Sonnax Reamer (#7754-R2 - $105-$140) to correct the valve body problem and replace the TCC regulator and sleeve with the updated parts. If they are familiar with the Sonnax kit to fix the 4L60E - they will also likely have the reamer already.

You do not have to drop the transmisson to have the valvebody fix completed - a knowledgeable shop can likely do it, but ask them before dropping it off (if you are not doing it yourself).

If you have the transmission rebuilt and they DO NOT fix this valve body issue - The problem WILL come back.

A short-term fix - when the harsh shifting occurs - pull over and turn off the truck for about a minute - then crank up the truck again and the harsh shifting is gone (for the time being) - this resets the valvebody and allows for normal operation again, but the problem will come back if driven for long enough again.
 

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ok i have a 98 Chevy Silverado 1500 4x4 Z71 with the 5.7L 350 and 4L60E Auto Trans

problem is, sometimes it will shift hard, the worst is from 1st to 2nd, and each gear its not as bad as the last shift, but around town its perfect, it will only shift hard if i drive nonstop for maybe 15 minutes or more so mostly after driving on the highway, interestate or country roads

now it doesn't do it all the time maybe every other time at the most, but if it start to do it all i have to do is pull over somewhere and cut the truck off for a couple minutes, then i crank it back up and it shifts perfect and couldn't be anymore smooth of a shift, so thats making me think its a sensor since when i cut the truck off and cut it back on is resetting it

i took it to Autozone last year (ya its been doing it for at least 2-3 years i just cut the truck off everytime it happens) the codes came up (can't remember and don't have the print out anymore) but i remember the solutions would be, crankshaft position sensor, camshaft position sensor, off timing, knock sensor and change the transmission fluid and filter, it might be a couple more but can't remember now since i can cut the truck off and back on and the problem stops completly i figure it should have to do with a sensor, i probably should replace the fluid and filter but don't have the money

so far i've replaced the crankshaft position sensor and the distributor which has the camshaft position sensor in it, so it has a new crankshaft sensor and distributor which i also had a new camshaft sensor in it so i didn't reuse the old sensor

so what other options is left other than the knock sensor and maybe changing the fluid and filter, now i don't have the money to fix it right now or at least take it to a mechanic, im just trying to get an idea of what else might be the problem, i might try the knock sensor though if it doesn't cost to much
" i probably should replace the fluid and filter but don't have the money" Yet you replaced the crank sensor and distributor. A transmission service would have been cheaper but most likely would not have fixed your concern. Believe it or not, you can save more money by taking your vehicle to a reliable shop. If you total up the cost of all the parts you will unnecessarily replace vs. the cost to have a professional look at it , you may begin to understand. The problem is most likely the valve body separator plate, or a leaking 1/2 accumulator. A skilled tech can repair that for about $5-$600. Transmission does not need to come out, and you get a free transmission service.
I do not suggest attempting this repair unless you have opened a valve body before. Do not look for the cheapest guy to do the job either. You wouldn't choose a doctor based on price alone, would you? Look for a certified shop that offers more than a 30 or 90 day warranty. Most reputable shops offer a year or more.
Remember, most professional techs have nothing in common with backyard mechanics. There is a huge difference between what we do every day and you do over the course of a weekend in your garage. The problem is there are a lot of hacks out there too playing mechanic. Check for reviews, ask friends and family, do a little research, and you may find that allowing a professional work on your vehicle may save you a lot of time and money. Just sayin...
 
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