440-T4/4T60/4T60-E

[Guest]

My question is the 440-T4/4T60 electronic or not. On B&M's website they have it listed as electronic since 88. In Chiliton shop manuel in the section for the car's wiring diagram it shows "Auto Trans Solenoids" and shows solenoids A through E. This manuel is for the C and H bodies. In '91 when the Park Ave. went full-er sized is when they started calling it "4T60-E" in the manuel it has the same "Auto Trans solenoids" but with the exception of the addition of F. (A-F) is now listed. Now I know the 440-T4/4T60 has the T.V. cable but what about the electrical diagram? Now for the H body F is listed, of course when it goes full-er sized in '92 and has the so called "4T60-E" I don't know. I once read an article that a GM Powertrain employer wrote about GM tranny he says they added electronic controls to the old 440 and made it a world class transmission.<P>Read this:<BR>> Here is the rough lineage of the 4T65-E:<BR>> Designed Yr.- Production Yr.- Model<BR>> <BR>> 1974 - 1978 - THM-125 (3T40) - Some bushings & bearings carried from<BR>> THM-200, some basic designs of splines & shafts from THM-200 and THM-350<BR>> <BR>> 1980 - 1983 - THM-440T4 (4T60) - Four speed version of THM-125. Some parts<BR>> identical or very similar. Somewhat stronger than THM-125.<BR>> <BR>> 1983? - 1986? - F-7 - Made exclusively for Cadillac Allante. Similar<BR>> design but many parts different to improve torque capacity. More<BR>> expensive.<BR>> <BR>> 1985 - 1988 - 4T60-E - (F-31) Electronic shift version of THM-440T4. Most<BR>> parts identical to THM-440T4.<BR>> <BR>> 1991? - 1993? - 4T60-E HD - Same as 4T60-E except with a few heavy duty<BR>> parts (mainly final drive gearset) for supercharged 3.8l V-6 application.<BR>> <BR>> 1992 - 1997 - 4T65-E - Very similar to 4T60-E with many common components,<BR>> but many major differences also.<BR>> <BR>> Below is a synopsis of a previous post with more description of changes<BR>> between models:<BR>> <BR>> A little history on the 4T60 used in FWD GM vehicles.<BR>> Best viewed fixed font.<BR>> The THM440-T4 was introduced in 1984 on the new GM<BR>> full sized luxury vehicles (Oldsmobile Regency 98, Buick<BR>> Park Avenue, Cadillac Sedan Deville - remember the logo<BR>> on the trunk lid "4-Speed Automatic"). This transmission<BR>> was basically the THM125-C with an overdrive added on.<BR>> The original 440 was not very reliable. Many changes<BR>> were made the first 3 years. Areas that suffered many<BR>> failures were torque converters (clutch rivets), 2nd<BR>> clutch housings, 4th clutch area, final drive.<BR>> When the Cadillac Allante was introduced, the 440<BR>> would not handle the torque of the V-8, so a special<BR>> version known as the F-7 was developed. It included<BR>> special sprockets, heavy duty final drive, special<BR>> fourth clutch, etc. A rare but solid transmission if<BR>> you can find one.<BR>> By 1988 the quality was better, but to make the<BR>> 440 (now called the 4T60) a world class transmission,<BR>> electronic controls were added. The new transmission was<BR>> coded F-31 and became known as the 4T60-E. The 4T60-E was<BR>> phased in from 1988 to 1990. You can tell by looking at<BR>> the bottom oil pan - it will be stamped with "4T60-E".<BR>> This transmission has much better reliability. By the<BR>> 1991 model year, all FWD Overdrive transmissions were<BR>> the 4T60-E model.<BR>> As a side note, with the introduction of the<BR>> Northstar V-8s, a new low volume transmission was<BR>> developed for these applications. It is known as the<BR>> 4T80-E. Very durable but very expensive, about 80%<BR>> higher in cost than the 4T60-E. Also 60 pounds<BR>> heavier.<BR>> With the introduction of the Supercharged 3800,<BR>> a few modifications to the 4T60-E were made. The<BR>> biggest change is the final drive unit, which is of<BR>> heavy duty design. The transmission still can't<BR>> handle the full torque of engines such as the SC 3800<BR>> and the DOHC 3.4L V-6s at redline during shifts. GM<BR>> utilizes Engine Torque Management to maintain<BR>> reliability. This consists of controlling engine rpm<BR>> and engine torque (through timing and fuel) during<BR>> shifts. That is why the SC 3800 and DOHC 3.4L do<BR>> not shift at redline at WOT.<BR>> For the 1997 model year, GM introduce the 4T65-E.<BR>> This transmission is a heavily reworked 4T60-E design<BR>> which includes such features as a 258mm torque converter<BR>> instead of 245mm, twin chains and special sprockets for<BR>> noise, Electronic Line Pressure (ELP) for ECM control<BR>> of pump pressure to better regulate shift quality,<BR>> revised fourth clutch, revised second clutch housing,<BR>> and many other improvements to reliability. The first<BR>> applications to receive the 4T65-E will be the<BR>> SC 3800 V-6 and the DOHC 3.4L V-6 to minimize the need<BR>> for torque management. The phase in will be three<BR>> years and will be complete by model year 1999.<BR>> The biggest cause of failure of the original<BR>> 4T60 (440) is heat. Through<BR>> control of shift points and torque converter lockup,<BR>> tranmission temperature can be controlled. There is<BR>> a temperature sensor in the transmission for the ECM<BR>> to monitor. This shows the STRONG recommendation<BR>> to add and external air/oil transmission cooler<BR>> for 4T60 (440) equipped vehicles.<BR>> The following is a list of GM FWD transmissions<BR>> and their applications:<BR>> <BR>> Model Years Current Application<BR>> --------------- ------------ ---------------------<BR>> THM125-C (3T40) 1979-2002 J (possibly to 2002)<BR>> 4T40-E 1995-future J,N,P-90<BR>> THM-440T4 (4T60) 1984-1990 None<BR>> 4T60-E 1988-1999 All except J,N,P-90<BR>> 4T65-E 1997-future SC 3800, DOHC 3.4L<BR>> 4T80-E 1992-2002 Northstar<BR>> <BR>> Steve Ochs aka N8TYS- Mfg. Engineer - GM Powertrain - Parma Plant<BR>> Transmission Division (4T60/65-E) - <BR>> The statements and opinions expressed here are NOT an official<BR>> statement of General Motors or the GM Powertrain Division<BR> <BR>Now read this: <A HREF="http://www.motorage.com/edindex/109814.HTM" TARGET=_blank>http://www.motorage.com/edindex/109814.HTM</A> <P>Now tell me what you think.<P>

[86 2dr.ltd]

What transmissions were used in the Eldorado and Seville and other caddys with the 4.1 and 4.9 or what ever they were?

[Guest]

1990 Reatta, tranaxle is 4T60, not the electronic variant. There are switches to tell the computer what gear it is in, and an electrical connection to the torque converter, but it is a hydraulically operated, including vacuum modulator. Is this because the electronic contols were not fully phased in? The manual does not list the "E" transaxle for either the Reatta or Riviera in 1990. Thanks for the input on why the engine "lays down" at the shift points. I always thought timing and fuel were pulled back to protect the transaxle.<P>------------------<BR>Hal, btk@vbe.com

[Guest]

No really a good answer, this time read my original message carefully.

[86 2dr.ltd]

Ive been reading but what transaxle was used in the other V8 Caddys?

[86 2dr.ltd]

Prior to the Nor-Star.The mid to 80's to early 90's Eldorados and Sevilles?

[Guest]

Oops, I missed the phased in part on the years 1988-1990 for the "E" variant. I guess that was part of my comment/question. The Reatta/Riviera must have been one of the last to get the electronic controls. Curious that, the Reatta was electronic for everything else?<P>------------------<BR>Hal, btk@vbe.com

[Guest]

The 4T60E was the first electronically controlled. But it was not fully electonically controlled until the 4T65E. Anything that says otherwise is wrong.<P>-T

[Guest]

What part was electronically controlled, if not the whole thing? I imagine 86 2dr is looking for a stronger transaxle without the electronic requirements, something I am curious about also. I'm not sure the early Caddy V8's had much more power than the Buick V6, maybe a little more torque, due to the cubic inches but about the same horsepower. Is there any way to upgrade the 4T60?<P>------------------<BR>Hal, btk@vbe.com

[86 2dr.ltd]

I just went to GM powertrain site and they list the 4T65E and 4T80E but thats today.At one time I was at a site that listed all the older Cadillac engines 4.1,4.3,4.9? I just dont remember.I did test drive a 90' Seville last year and I mean to tell you it had some power and that was not the 4.9 but I now dont remember, 4.1 maybe.Ive got to believe they had a heavier trans behind that 4.9.

[Guest]

O.K. I guess I have to clear this up the Caddys had the 4T60 with a viscous-type torque convertor and heavier final drive assembly. The 4T60-E you are referring to is 91-up it differs in the way of the vacuum modulator on the front of the transaxle which controls the shift quality (firmness), The 4T65-E is completely electronic with a electronic shift quality is controlled. My question is about the 440-T4 and 4T60 where it didn't yet have the "E" designation. Beside the h.p. on the 4.5L V8 was only 150 less than the 3800!! The 4.9L V-8 had 200 h.p. the 440 can take 100 (about) neutral drops at 5000 rpm my friend did it on his 3.8L on his '86? or '87 Cutlass Ciera untill the timing chain suffered.

[86 2dr.ltd]

So when people tear these transmissions up what is it that goes?Is it usually the same failure or are there many weak points.Ive seen alot for sale with "new trans",or "needs trans"yet many go 200,000 with no problems.I'm guessing its the final drives or torque convertor because if the 440T4 and 4T60 are the same and guys are putting the 440T4 in old RWD cars for the overdrive why would they do this if it were weak?<P>Ours with our small 3.0 has been fine with 150,000 miles.It does and always has had the annoying convertor lock up substance abuse problem.I'm guessing it has the 4T60.

[86 2dr.ltd]

Sorry, ignore what I said about 440-t4 in RWD.I see my mistake> I confused 440-T4 with 200R4.

[Guest]

Did you see that post on your 3.0 it has all the specs listed. The 440 isn't weak it's just not maintained. Change the fluid via a powerflush every 15,000 miles.

[86 2dr.ltd]

Yes,I saw it and thanks for all the infomation and links,although that computer link is above my head.That power flush is quite expensive.Not that I'm saying you can put a price on preventive maintenance but it seems like there is a little bit to much capitolism going on there.<P>I'm still looking to hear about what is the weak link on these transmissions.To bad they didnt get right on it the first year.It would have saved GM the reputation of transmission problems.GM does deserve credit however for putting quite large and powerful engines in a FWD drivetrain.As the problems all seem to be related to the fact that the larger engines have to much torque and in FWD space is at a premium.They still should have gotten on it,they knew the problem was there.Rumors have it that the LeSabre GN had apparently proved this in 85? when a turbo charged prototype ate the trannies up!Now the guys that are into the older FWDs that are trying to build em up a little cant simply find a bigger engine or build it up they need to get a whole drivetrain because the transmissions are borderline to begin with.

[Guest]

86 2dr, if you want to get rid of that annoying early torque converter lockup, I can send you a modification to the electrical connection to the transaxle. I have searched for a source for the original modified cable I purchased years ago, but have come up empty. The only requirement is a transistor, a resistor and a little soldering. This can be installed in the original harness. All functiona are retained, but lockup can only occur in 4th gear. It really helps the 35-45 mph speed range by keeping the rev's up so response is better.<P>------------------<BR>Hal, btk@vbe.com

[Guest]

The reason for TCC lockup at 35 or higher is to prevent power loss. I wouldn't change any of it. And the weak parts are on my original posts.<BR>

[86 2dr.ltd]

I thought it was for gas milage.Its annoying and frankly stinks.It just cant make up its mind.Its hilly here and this car unless on highway we dont even put it in overdrive.When we do it really cant make up its mind.I'll be getting back into it this spring Hal so I'd like to try what you have.

[Guest]

Chuck is right to a certain extent, the torque converter will have more "slippage" at speeds below 4th gear (about 50 mph. on my car), which will cause the oil temperature to rise somewhat, however, we are talking about low speed, low load cruising. I have had this device for over five years now, and have enjoyed the result. I do service the transaxle regularly, every two years which is about 8000 miles, and have never noticed any problem. It just so happens most of my urban driving is in the 35-45mph speed range and keeping it out of lockup in third gear, raises engine rpm two to three hundred. This puts it right close to the torque peak of 1900-2000 rpm, which perks up responsiveness. Anything can be abused, but it's a question of lugging the engine or adding slippage to the trans. in a narrow speed range. Pick your poison. Personally, I would think the hunting is more harmful.<P>------------------<BR>Hal, btk@vbe.com

[86 2dr.ltd]

I see.I know nothing about autos.We always had standards.The auto is nice though but more complicated and expensive when it goes

[86 2dr.ltd]

Did the older THM350's and 400's have different type of torque converter.They didnt have this lock up thing going on and 35-40 mph never bothered them.What about a way to controll lock up manually?Its just to darn annoying. Our 89 Chrysler has a 4sp. and it doesnt do this.Maybe I've got some other problems that make this worce than it needs to be.

[Guest]

No, the THM 350 and 400 did not use a lockup converter, but then again they are generally heavier in their construction and RWD to boot. The lockup feature allows for more efficient cruising and less heat build up in the more compact construction. Modern descendants of the 350 and 400 do use lockup and a 4th speed for efficiency under cruise conditions, even in pickup trucks. When you step on the brake or accelerate briskly, the lockup should disengage, so sometimes what you think is a downshift actually is the torque converter unlocking. You may try a fluid and filter change. When I first bought my car it sometimes hunted, it felt like an upshift and then downshift, also very rough going into reverse. A fluid and filter change seems to have made all the difference, (maybe a sticky servo?) At the very least, when the pan is pulled, you will be able to check the condition of the interior. Looking for clutch material or metal dust. If I remember correctly, a couple of friends had a kit of some sort installed which cured the hunting problem but they were both four cylinder fwd cars. You might try contacting a reputable transmission shop for advice.<P>------------------<BR>Hal, btk@vbe.com

[Guest]

Just a note while we're here:<P>The TH350 was indeed available with a lockup convertor, from approx. 1981 to ??? when 3 speed rwd production ceased.<P>Their lockup is very simple. It uses a 12V source, a brake pedal switch, and a vaccuum switch all connected in series. This is what I based my lockup circuits on for the older 700R4/200-4R conversions. <P>One could easily add a toggle switch to either circuit. For your hilly roads, just leave it off. Head to the hwy and flip it on.<P><P>------------------<BR>1968 "Canadian" Pontiac Beaumont<BR>1988 Buick LeSabre T-Type<BR>

[Guest]

DOH!, you're absolutly right Derek. Just being a three speed doesn't mean it can't have a lockup for the converter. OOPs.<P>------------------<BR>Hal, btk@vbe.com

[Guest]

Does anybody have an answer to my original answer. If the tranny has the letter C after it is electronic locking.

[Yasir Dahham]

May I inquire about a transmission (transaxle) of my car. It is a 4T60 E transmission mounted on my Pontiac Grand Am Model 1995 having a 4 cylinder QUAD4 DOHC engine. Lately, the 4th speed is never there, the engine is revved more than 3500 RPM with speed of car around 100 -130 km/hour, yet it is only the same 3rd speed because the engine is screaming. Any idea what caused this failure and how to check  or track it?

[NTX5467]

If it is an electronic-controlled transaxle, there could be a pressure switch on the valve body that is not working.  Usually, each "gear" ahs a pressure switch to shift into the next gear.  Need to see a competent transmission shop for such things as "some disassembly required" for that repair.  Plus a new fluid and filter.

 

If it is a non-electronic shift transaxle, then it could be a governor and/or valve body issue.  Again, "some disassembly required" by a competent transmission shop.

 

Regards,

NTX5467

[EmTee]

Some of those early '90s GM transaxles had lock-up torque converter issues and I've seen a few that have had the wire to the transaxle that controls the lock-up purposely disconnected to stop the car from stalling at a traffic light when the torque converter clutch fails to release.  If the lock-up function is bypassed, the transmission will not shift into OD.

[NTX5467]

The Turbo 200s were bad about the lock-up switch failing and the cars stalling every time they came to a stop.  About a $30.00 switch at that time.  Sold lots of them in the 1990s.

 

NTX5467