4L60E Trans Shifts hard from 1st to 2nd?
 

Hi All!

I have a 93 stepside with 4.3 engine and a 4L60E trans, it has been rebuilt 1 month ago and still shifts hard from 1st to 2nd only, other gears shift fine.
When it is very cold outside it shifts great, but warm outside shifts hard from 1st to 2nd.


Any ideas???????


Jeff
Pensacola, FL
850-475-5030

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

What did the rebuild shop use for the valve body? Did they yse a shift improver kit? If so, then you may have a set of spring loaded chck balls that are upgraded to have it shift harder. Also the Governor may have been upgraded to a "Corvette" style governor, which will enhance the shift.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

I had a 1993 4.3 W/T with the 4l60e. From 1st to 2nd it would snap your neck. It always shifted like that. I had the tranny rebuild, and it still shifted that way. A friend, that works on transmissioons, somehow found out that this was a problem that GM had. There is a repair kit for this. It has something to do with either replaceing a spring in the valvebody, or just cutting down the existing spring.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

I had a shift kit put in my 4L60E when it was rebuilt two years ago and it did the same thing afterwards. Then I put a round bale in the bed and it shifted smooth as silk.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

It's characteristic for the 4L60E to shift hard between 1 and 2. You can, and I would, recommend a shift improver kit. It helped mine immensly. When I first got the truck, with the way it shifted, I figured the tranny would not last long. But everyone that I talked to said they had the same problems with that particular tranny. When I redid my engine and had the tranny out, we added the kit. Later on I decided to rebuild the tranny as I had it out of the truck again. One thing I did notice, and I am not sure what it is called, but it is the drum that the clutch pack sets into, was belled out a little at the top and closer inspection revealed that it was cracked. My nephew who is a certified mechanic said that he has seen that quite a bit in the 4L60E's. from what I seen, it is or appears to be, cheaply made from the factory. But the shift improver kit did help a lot and was worth it. I'm just glad I looked at rebuilding the tranny later on though. And one thing to remember.....the kit is a "shift improver" and not a "shift kit" like used to be put in the Turbo 350's and Turbo 400's. This kit will smooth the 1-2 shift and not make a neck snapping shift.

Kevin

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

There are a couple of places the 700R4/4l60/4L60E (all basically the same units) trannys suffered. The valve body has seperator plates in them that the balls work against. These plates are not hardened from the factory and they suffer after awhile and the holes become wallowed out. That in itself will create a bad shift. The planetaries on the trannies are also a problem, with age. These can be replaced with hardened stronger units that causes the transmission to work better. As for shift imporver kits, I would look seriously at the TRANSGO kits, they are far more involved and better designed than the ones from other suppliers.

I prefer a neck snapping shift in the 1 to 2 gears, I want that gear to engage and hold, which means there would less wear on the bands, due to sloppy shifting. I have my trucks and my wife's Impala Ss set u p to do just that.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

That's what I have in mine. Not a neck snapper but not a slider either.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

I have way more than the TRANSGO in my trannys. That is what we used to make the valve bodies work better. The other gaggle of parts from the new planetary, to the five sprocket sun gear, hardened seperator plates, and the 9 pack clutches make up the rest of it. Add a Corvette Governor and the tranny is now a Chiropractor working on your neck and attitude.

The transgo will give you a solid shift and update your shift program seriously, for a little more money than some kits, but is definitely complete. It even has a video on how to do it and what to expect.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

I had my 700 rebuilt & it doesnt shift hard at all, but I wish it did. It shifts way too soon for my taste too. I think Ill look into a shift kit for it...

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

Look into upgrading to the Corvette Governor, it made a severe change in my Son's truck.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

This shift improver kit easy to install yourself? My truck has been doing that for along time now. Hardly in the winter but alot in the summer time after driving for long periods of time. Where can i get such a kit from? Thanks

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

Go to Summit Racing at this link and see what they have. http://store.summitracing.com/partde...5&autoview=sku

The kit sells for 129.00 and includes a video for assistance as well as instructions.

Been there - Done that!
 

I had the same problem awhile back...

After driving for about 30+ mins the car starts to shift violently on the 1-2 upshift and if not corrected it would throw a SEL (Service Engine Light) with a code of P1870.

What many mechanics will say - bad tranny, needs rebuild, needs replaced, etc. If your tranny has 130k miles on it then - yes- it may need a rebuild by now, but that is not what is causing the harsh 1-2 shifting when warm.

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 - quarter of the way down - after #43G. **NOTE: I have no affiliation with this website nor have I ordered anything from it - I merely used it as example to demonstrate the parts and their numbers

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)
http://www.transmissioncenter.net/77754-r2.jpeg

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.

Hope that helped- now back to my turn signal problem...

Tom

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

hey, want to dig this one back to the top. Anyways, my truck's been shifting hard (1 to 2, hard; 2 to 3 okay; 3 to 4 just a little hard shift) and threw me an engine code (it's done it before, once, I'm guessing it's the same code for the tranny) and with 130k miles on it, I'm sure the tranny's trying to tell me she's gettin old and worn out. I pulled the dipstick to make sure, the tranny fluid smelled kinda funny, and there were chunks of material on the dipstick, assummingly pieces of my clutch packs.

So I'm figuring I'm going to have to have my transmission replaced (which would happen in a few years anyways, so might as well get it done now). So when I go down to the Clutch and Transmission shop, what should I ask them for? A stock tranny would work, but you guys were talking about these kits... now, this thing is my DD, and I'd like it to shift rather smooth, ya know. Don't want to be just cruisin the main drag, and at every intersection be snapping my neck, just at a normle take off (now, a full throttle take off is different, but that's a different story).

So my question is, while getting a reman'ed, or rebuilt tranny, what should I request for it? Anything special? Just ask for a rebuild? Ask if they can get me a rebuild and put some stuff in it?

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

Surprisingly enough, you can rebuild a tranny yourself. I helped the guy rebuild mine. I was always intimidated by an automatic tranny for fear that something would go horribly wrong. But with helping him and the book that we had, it went really fast and simple. I would definately do the next one myself. Just make sure you have a large clean bench to do it on, and either a parts cleaner or a 5 gallon bucket with parrts cleaner in it. Should take one evening to tear it apart and clean it and one evening to put it back together.

Kevin

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

Decide on how your drive your DD. Do you drive it like a normal working stiff, or do you want a little performance and sharpness in the shifts (designed to be there)? I have had a couple of trannys reworked through my local buddy and his shop and for them, we chose to upgrade the internals to heavier duty clutch packs and the valve bodies have been upgraded to the harder seperator plates (common problem with 700s and 4L60 trannys). On my DD truck (as well as my Sport truck) I spent what I could to get the heavier duty planetary, sprags and gears; along with the upgraded shift kit. I run my truck around 21,000 miles a year in daily use and want it to shift solid and quick. The improved shifting should help with the life of the clutch packs, less slippage on each and every shift controls the wear. A soft sloppy shift allows the clutches to slip and wear is created. I also added a "Corvette Governor" to assist in the shifting and m aking it where the truck would shift under acceleration, when needed.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

what I need is a tranny that's meant for a DD, but won't slip and ruin the clutch packs again. I might be able to do the tranny myself, also. One of my buddies has a shop, needs some work, but I could use it if we cleaned some of his family's stuff out of there (believe me, anybody here would have a hayday there, motors, trannies, carbs, books, woodworking stuff, metal working stuff, pipebender, tools, tools, tools, more tools, some more tools, lots more tools, did I mention tools?, sure I didn't mention tools?, cool stuff stashed everywhere) and just cleaned the main area a bit, drilled into the concrete and bolted the lift down, fixed the one garage door and set it up. Not a lot of stuff, just easy and slightly-time consuming, and I know he has every tool imaginable to do almost every job on any truck or car.

So now I just need to figure out what to put in the tranny, or whether I should just go crying to mom and dad to pay for a generic reman from the local tranny shop. This thing will be my DD, but my DD is also my play/work truck, when I need it to be. It sees quite a bit of offroad time, especially in the summer, and during hunting season. It also sees what work I need to do, although it's not often that I have to haul anything around (it started it's life as a camper truck, that could be one reason for the tranny going this early). But it does see some main-street powerhousing, so it's gotta be something that'll withstand:

a) a hard trail; steep hills; thick, slick, and s**t mud; snow, etc.
b) a good load, car trailer w/ two ton car on it (although it'll rarely ever see that, due to the suspension
c) the almost daily main drag hardships of seeing a rice-mobile and putting those 265 ponies successfully into making both wheels spin out back

this thing will see more than it's share of stress, I'm sure, so it's gotta hold it, plus it's gotta shift decently smooth, not hard to snap my neck EVERYtime, but not so smoothly that it slips the clutches. I'm not a tranny guy, but I know some of you people are, so what's your advice?

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

A factory reman is NOT in your future. Those things are not built for longevity, You need to get into a tranny shop and have the guy get you the heavy duty parts in at least the clutches, governor, and valve body parts (seperator plates and Sonex valves). The planetary and sun gears are another thing that is relatively weak in these trannies and are known to explode. That is why I chose to upgrade.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

My 1993 Sierra has the opposite problem - shifts hard between 1st and 2nd when cold, but smooths out when warm. Could it be the tranny fluid and filter needs changing, or is this just a different version of the same problem everybody else has? Any ideas? Thanks!

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

:welcome2: from the Heart of Arkansas!

Looks like you been wandering the halls of old posts, looking for some help. We also have a separate forum just for engines and drivetrains. You might consider a new topic post on that forum and see what happens.

As for soft shifts, I don't have any answer. How long has it been since your transmission was serviced? Usually, 60K mile intervals are recommended. My experience with filters that are getting past their prime was limited to my '64 Bonneville, about 40 years ago. In that case, I'd back it out of my parking spot, shift to drive and wait for everything else to make the shift, too. Changing the fluid and filter fixed that problem.

Re: 4L60E Trans Shifts hard from 1st to 2nd?
 

Thanks for the direction - I'm new and I'll check out the engines and drivetrains forum.