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01 4t65e tranny shudder problem

B

billy101

New member
Hi guys, I'm new here. I'm a regular member over at News - NAIOA and I posted my problem over there but it's not getting much help. This forum looks a lot more active so I thought, let me post it over here! Here is a copy & paste from my thread on NAIOA. Thanks in advance guys.
The car is a 2001 Chevrolet Impala LS 3.8 with 116,289 miles on it as of 6/20/2011.

Here starts the long ass story; sorry!

I've been doing a lot of highway driving lately and I've been noticing after driving 70-85mph for awhile, and then slowing down to city speeds 35-55mph, the shifts are pretty slow/sloppy, and the tranny is whining VERY loud, throughout 1st, 2nd and 3rd gears. I'm guessing that's the PCS whining? If I turn the car off for awhile and let it cool off and drive off again it's still loud, but the shifts are back to normal and it's all good. Okay, now where it gets bad. Friday afternoon, backing out of the garage into the road, and then I put it in Drive. Upon giving it gas it shuddered like hell and up until 3k rpm it barely moved, and then SLAMMED into gear and spun the tires...so much that traction control engaged. It did this two more times as I was leaving my neighborhood, and then drove off fine, and has been driving fine..even drove 160miles on the highway and it didn't hiccup once..just the tranny was whining loud as hell like usual. It has been giving me problems with slamming into gear after not being driven for awhile (usually after sitting overnight) for a long time now.

My car just rolled over 116k miles, its at about 116,251miles right now.

I was wondering what route would be best for me?

Should I attempt at replacing the PCS, and while having it all apart, doing the shift kit while I am at it? http://www.ls1tech.com/forums/.....movie.html That link makes it seem pretty simple and straight forward to install the kit. If installing the kit along with replacing the PCS as well as whatever else is easy to get to when I'm down there will give me little longer on this tranny PLEASE let me know.

Other than what happened on Friday, it has been shifting PERFECTLY for the last 116k miles of the transmission's life. The torque converter still locks up great, never surges, 4th gear is still intact...

Thanks for the help in advance, and sorry for the long ass story...this car's my baby and I would hate to have to get rid of it.


Here is a link to the thread on NAIOA.
http://www.naioa.com/v2/modules.php?name=Forums&file=viewtopic&t=44674

Thanks again!
 


Whining is typically a sign that the pump is starving for fluid. Have you ever had the transmission serviced?

The harsh engagement/sloppy shifts could be a sticking valve etc. Typically the PCS will toss a code and give you max adapt shifting based on pressure issues. The rest of the behaviors you have described don't really fit with the pcs.

BTW, to get to the pcs you need to lower your trans mostly out of the car to get the side cover off.
 
BillBoost37 said:
Whining is typically a sign that the pump is starving for fluid. Have you ever had the transmission serviced?

The harsh engagement/sloppy shifts could be a sticking valve etc. Typically the PCS will toss a code and give you max adapt shifting based on pressure issues. The rest of the behaviors you have described don't really fit with the pcs.

BTW, to get to the pcs you need to lower your trans mostly out of the car to get the side cover off.
Click to expand...

Unfortunately no the transmission has never been serviced in it's life. I check the tranny fluid on a monthly basis and it's not too dirty, it still has a red/pinkish hue to it. If the PCS is starving for fluid could the filter be dirty? After this whole big ordeal last week something made me remember that the MAF sensor has something to do with line pressure so I went out and got some CRC MAF sensor cleaner yesterday and I cleaned the MAF for the first time, and some black stuff came off of it. I'm not sure if that helped at all.

What would explain the shuddering that happened? I don't have a code reader that will read transmission codes, would a tranny code trigger a CEL?

I know that getting to the PCS requires the whole left side of the subframe/cradle to be lowered a bunch, I was prepared for that.

If it's starving for fluid should I make an attempt at dropping the pan, removing the accumulator and installing a shift kit to reduce slipping on the 1-2 and 2-3 shifts, and then replace the filter and then close up and refill her up?

What I'm trying to do is, being that the tranny has never been touched in 116k miles while I'm going to have it apart should I just replace the PCS along with any other solenoid/sensor that's easily accessible just so I make sure they don't go bad once I close the tranny back up and have to tear it apart again?

Thanks
 
Wow.. you have some info, sounds like it's kinda mashed together in a random order though. I've never read or heard of Maf controlling line pressure, it is used to determine shifts etc along with TPS.

Since the trans is still a young transmission. Drop the pan, change the filter and refill with one quart of Lucas trans stop slip and the rest Dex 3 regular fluid (no syn).

A whining from the pump starving for fluid can easily be a clogged filter.
 
BillBoost37 said:
Wow.. you have some info, sounds like it's kinda mashed together in a random order though. I've never read or heard of Maf controlling line pressure, it is used to determine shifts etc along with TPS.

Since the trans is still a young transmission. Drop the pan, change the filter and refill with one quart of Lucas trans stop slip and the rest Dex 3 regular fluid (no syn).

A whining from the pump starving for fluid can easily be a clogged filter.
Click to expand...

Thanks for the fast reply. I know I'm sorry I mashed a bunch of stuff together. I'm only 16, almost 17 and I've read all the horror stories about these 4t65e trannies and I almost teared up Friday afternoon when it started shuddering....I love my car, it was given to me by my parents when I turned 16 and it was my mom's car babied since we purchased it brand new in 2000.

You don't recommend putting in a shift kit? I've read that it's super easy to do and is usually a good preventative measure.

If you don't recommend putting in the shift kit, I will most definitely drop the pan, replace the filter and refill with what you told me to. Any reason why you didn't say to put Dex 6 in?
 
I'm all for a transgo shift kit. Except I don't think it's going to help your current issue. Therefore I didn't suggest spending the extra money w/o a need.

I've heard mixed reviews on Dex 6. Some seem to experience slippage with it. Who knows if they already have issues or not. So being that dex 3 is lower cost and proven to work well, it seemed like the better recommendation. Synthetic versions of dex 3 have also given mixed results...once again.. who knows the condition of the trans.

I'm about to try out Dex 6 Walmart brand in a trans I recently built. Til I have some long term results... I don't like to suggest mixed result things.
 


BillBoost37 said:
I'm all for a transgo shift kit. Except I don't think it's going to help your current issue. Therefore I didn't suggest spending the extra money w/o a need.

I've heard mixed reviews on Dex 6. Some seem to experience slippage with it. Who knows if they already have issues or not. So being that dex 3 is lower cost and proven to work well, it seemed like the better recommendation. Synthetic versions of dex 3 have also given mixed results...once again.. who knows the condition of the trans.

I'm about to try out Dex 6 Walmart brand in a trans I recently built. Til I have some long term results... I don't like to suggest mixed result things.
Click to expand...

Alright, Dex 3 sounds good then.
Although the shift kit may not help the issue I'm trying to get it to last as long as possible before HAVING to get it rebuilt.

Which shift kit would you recommend?

THRASHER Shift Kit for your 4T65e - from the home of Thrasher Engineered Performance

I've read great things about the intense one..
INTENSE-Racing.com: INTENSE™ Street/Strip Performance Shift Pak®


I would follow this how-to.
Shift kit install, very detailed (56K go watch a movie) - LS1TECH
 
BillBoost37 said:
Upgrades

bottom of the page. Transgo shift kit.
Click to expand...

Alright, nice! Thanks for the link.

Should I go with the 64.95 one or the 89.95 one?

As far as I can tell the 89.95 one doesn't have gaskets. I'm pretty confused on what the differences are between the two. Should that how-to I posted work well? and does the Transgo shift kit include instructions on the shift firmness, etc?
 


There's 20 10mm bolts that have a torque of 120inch lbs holding on the pan.

If the gasket has ridges in it and metal, it's a factory lifetime gasket. Reuse it.

The accumulator is held on by 5 8mm bolts. The accumulator torque is 97 inch lbs.

The 2-3 and 1-2 accumulators are labeled on the bottom cover of the accumulator.
 
BillBoost37 said:
There's 20 10mm bolts that have a torque of 120inch lbs holding on the pan.

If the gasket has ridges in it and metal, it's a factory lifetime gasket. Reuse it.

The accumulator is held on by 5 8mm bolts. The accumulator torque is 97 inch lbs.

The 2-3 and 1-2 accumulators are labeled on the bottom cover of the accumulator.
Click to expand...

Thanks for that information. The kit comes with instructions on the shift firmness right?
 
BillBoost37 said:
Should, or it's one firmness.
Click to expand...

Okay, that's all the information I need right now.

Thanks for your help, I really appreciate it! Sounds like me and my dad have a project one night this week, or a weekend project! :)

I'll update this thread if I have anymore questions!
 


BillBoost37 said:
It's about an hour to two if it's your first time out. That's as long as you dont' find "parts" in the pan.
Click to expand...

I think the tranny is in good shape, I hope there aren't any metal parts in the bottom of the pan. I've taken a magnet to some of the fluid and there aren't any metal shavings in it so that's a good sign. We have a Snap-On lift in our garage and you can almost stand under it so it should make this a rather easy project.
 
BillBoost37 said:
Now I hate you. :D
Click to expand...

Haha I'm sorry! My dad's been a Subaru Certified Technician for 26+ years. He works at a Hyundai Subaru dealership working on Subarus everday of his life. He does side work for play money out of the garage. So having the lift in the garage has helped him so much.

Here's the imp up on the lift getting waxed along with a tire rotate and brake change. :)

IMG_20110318_194353.jpg

IMG_20110318_194255.jpg
 
I've never read or heard of Maf controlling line pressure, it is used to determine shifts etc along with TPS
Click to expand...

The MAF has a direct effect on transmission line pressure. A dirty MAF can cause low line pressure.
Something else on this note- Changing/Upgrading your MAF sensor to a larger one, porting your throttle body, larger intake piping ALL effect MAF signal. When you make the pathway larger you slow down airflow across the MAF sensor and guess what- lower trans line pressure, especially at WOT on the high end of the scale. Not something you think about but when you experience it first hand and see the results you never forget.

Should I go with the 64.95 one or the 89.95 one?
Click to expand...
We started to offer a Combo Kit for the Transgo Shift Kit as it includes a new filter and required gaskets to install the shift kit. The basic $64.95 kit is considered a rebuilders kit and does not include any gaskets. As a bare minimum the accumulator body gasket should be replaced if you are going to install any shift kit.

As Bill said above the shift kit will help to clean up your shifts but is not going to address your whole problem. The whine noise could be a number of things. You mention it happening in gear, but does it make the noise if sitting stopped while in gear? There are a lot of posibilities and some are fairly common in these transmissions that will cause a whine. Also check your engine accessories and idler pullies- they can fool you and make plenty of noise and a stethoscope will help isolate the source. Your slippage on take-off and banging into gear could be result of a few other problems and most likely worn seals and worn input clutch apply piston as this is fairly common. Here is more info on this- No Forward Cold
 
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