HD2 kit Update and caution
recently we had a discussion on the sloppy page and people pointed out to me to not perform this mod
"Grady Farrer: It's to solve over pressure conditions. It has you drill from 14 into 47. 47 is a void so it's easy to undo this mod if you've already done it
If torque signal fluid builds up too much pressure (tune. Worn valve. Epc, etc) then it will unseat the trans go ball and exhaust the fluid.
This way you don't build up too much pressure and blow out snap rings or seals etc.
It's a bad mod because if the transgo ball doesn't seal perfectly...or over time it wears out and leaks...or gets cocked sideways etc...then it leaks torque signal fluid and causes horribly LOW line pressure and cooks the trans
It doesn't really fix anything and there's a big risk to break shit. Moral of the story... don't do the relief mod
4.8/5.3 4L80E Swap & General Information
'91 -'96: They are all pretty much the same. They were also known to have a crappy connector that passes through the case. Most have had them updated by now, but there are still some that haven't and might need replacing. They have the ‘older’ style lubrication, where both cooling lines are behind the bellhousing. They also have larger overdrive roller clutch, usually came with a 16 element sprag instead of the 36 element. The bellhouse bolt pattern is the traditional SBC/BBC pattern. These early transmission also did not have mounting holes for the manual lever position switch (MLPS) ie. neutral safety switch.
'94 -'96: These are the same as the earlier ones but with a few differences. It has an updated EPC (electronic pressure control) solenoid. Some also had a longer shift shaft for the MLPS.
'97 - '99: These years have the ‘new’ style lubrication, where there is one oil cooler line behind the bellhousing and the other being farther towards the back of the transmission. Also uses the bellhousing bolt pattern of previous years.
‘00 - ’03: Same as previous years but bellhousing bolt pattern was changed to the LS style.
‘04 - up: Same as previous year with some minor valve body changes.
You will need a flexplate and spacer from ¾ ton GM truck that originally came with a 4L80E. Your other option is, if you're going with an aftermarket torque converter anyways, is to have the torque converter made with the correct offsets and mounting pads to bolt up to the stock 4.8/5.3 flex plate. Circle D can do this no problem. (https://www.circledspecialties.com/)
GM Part Numbers:
19257940 BOLTS 6
If you’re using the factory PCM this is pretty straight forward, just have it loaded with a 80e tune from a Chevy Express 4.8/4L80e or similar.
DIY Manual Valve Body:
Terminal pinout wires "A" and "B" from the pressure manifold are connected together and connected to the ground side of "Shift Solenoid A". Terminal pinout wire " C" from the pressure manifold is connected to the ground side of "Shift Solenoid "B". 12 Volts is supplied to the Pink Wire on the outside of the trans .This will power up the shift solenoids as well as the lock up solenoid. If you want to lock the converter you must run the Brown Wire on the outside of the trans through a toggle switch to chassis ground.
‘91 - ‘96 (SM=Straight Mechanical)
‘97 - Up (SM=Straight Mechanical)
Note: They are straight thread without the taper normal pipe thread has. Also on later models (‘97 and up) the rear cooling line fitting has an extended tube that goes inside the transmission, looks like so -
Info was grabbed from multiple sources
among others I can’t remember
Tips for building a 4l80e without the HD2 Kit (By Grady):
If you're going to tear the trans down to a bare case and actually build the thing...don't spend your money on the transgo HD2 Kit. The transgo kit does 2 main things...increases line pressure and "dual feeds" the direct clutch.
The direct clutch is used in 3rd gear and also for reverse. The apply piston for this clutch is divided into two chambers. In reverse, it uses both chambers and gets full apply force. In 3rd, it only uses one chamber...significantly reducing the apply area and overall holding power. "dual feeding" the clutch allows both chambers of the apply piston to be used in 3rd gear also...more than doubling the strength of 3rd gear.
To dual feed...remove the center lip seal on the apply piston, remove the 2nd sealing ring on the center support, and plug the case hole to the right of the center support bolt. You can plug the case passage with a 3/8 cup plug driven in. Or you can tap the center support and install a set screw. Make sure the set screw is below flush otherwise the center support won't seal against the case and you'll have a nightmare.
For increasing the pressure, use a sonnax brand boost valve. The "4L80e-LB1" is the part number you want. If making LESS than 1khp...and I mean a true 1khp to the tire...use the valve and sleeve but keep the stock pressure regulator spring. If making more than 1khp...use the included sonnax spring.
Another important area to improve is the intermediate clutch snap ring. The stock ring is flimsy and weak. Use a snap ring from a Torque Flite 727. the 0.106 thickness option usually works the best. if clearance is too tight with the .106 you can step down to the .088
Drill the separator plate. I've attached the transgo plate picture so you can see which hole is for which gear. Usually 5/64" (.078) is fine for lighter cars or lower power units for 2nd gear...you don't need to make 2nd stupid firm. If making some jam or in a heavy vehicle (4k+ lbs) 3/32 (.093) will be ok. 3rd you can go 7/64 (.110) for most stuff and for high hp/heavy go 1/8" (.125) Same for 4th.
Don't take these numbers as gospel...it varries car to car, engine to engine, and person to person. While uncle Jimmith might want to "bark the tires" on every shift at 20% throttle...other guys might not want that.
Bigger hole=faster/firmer shift. If you block accumulators...use the smaller of the hole options because the shifts will get faster and firmer when you block accumulators.
As a side note...replace the electronics and harness. You can usually do this for less than $200. If nothing else...replace the EPC solenoid. It is by far the most important as it controlls the pressure of the trans. So just replace it...don't cheap out here.
Speaking of accumulators...if you want to block the 3rd or 4th accumulators, you have a couple options. The first option is the easiest and most foolproof...just buy an accumulator delete plate from Jakes performance. They're not that expensive and they work great every time. If you don't want to buy one, you can tap the stock accumulator housing and block the feed holes with a set screw. The bore without the pin is for 3rd. The hole with the pin is for 4th. the 2nd accumulator is in the case and does not need to be blocked. Use a 5/16"-18 tap and set screw.
Ideally, you would have the pump and valve body vacuum tested...but I'm realistic...99% of guys in their shop aren't going to do that. SO, just buy the transgo AFL Fix kit. "48-ACT-TL"
The kit will do 5 valve bodies...so save the kit and do a solid for some local buddies or sell the used kit with 4 valves left in it...it ends up being very worth the cost. A leaky AFL will cause HORRIBLE pressure rise, and poor actuation of the shift valves...which means the solenoids might command a gear...but the pressure from afl is too low and it won't move the valve and shift.
Also, in the pump, drill this hole. But use a 5/64" (.078) drill bit. It provides better lube flow...it also keeps the converter from dragging. So, you'll run cooler, have better lube, keep the converter happy, etc.
As a rule of thumb...over 700 horse...get a billet input. Jakes performance has a budget friendly billet shaft.
over 800 horse get a forged fwd. hub...FTI has a good unit at a good price. (if you're building a 400...they have a weaker hub...use an 80e steel hub up until 800 horse...then go forged)
MOST IMPORTANTLY Verify the damn fluid level. Seriously...you've taken the time to 80e swap your ride...you've LS swapped your shitbox, you've loaded a tune from the sloppy wiki...you've done alot of stuff that has taken more time and energy than this...but this can EASILY ruin your weekend when you shit a trans.
Just make sure the dipstick reads correctly. Correct reading means that "FULL" Is level with the pan rail. The flat part of the case where the pan bolts/seals. Right at that level or 1/8" above it the correct fill level. I recommend doing it IN THE CAR with the dipstick permanently mounted. Get the trans in and bolted up to the cross member...then drop the pan and check the stick. Scribe a line on the stick if the existing line is not accurate. It doesn't matter if you get a "madman" or a lokar or some other 200 dollar dipstick...don't assume it is correct...verify it. Honestly this is one of the biggest killer of fwd and int clutches and it's ridiculous not to take the time to do this verification step.
How much power can the 4L80E handle? A totally stock unit or rebuild will typically live well with up to 450 flywheel HP/TQ. Above this point the direct clutches will not live long without some hydraulic improvements.Are all 4L80 torque converters the same? ›
'91 -'96: They are all pretty much the same. They were also known to have a crappy connector that passes through the case. Most have had them updated by now, but there are still some that haven't and might need replacing.
The 4L80E offers several significant advantages for a wide variety of applications. The 0.75:1 overdrive ratio provides a significant reduction in cruising RPM which will help contribute to a dramatic increase in efficiency.Can you run a 4L80 without a computer? ›
The only downfall of this swap is that the 4L80E is an electronic transmission that generally requires an additional computer and wiring harness to operate properly.Can a stock 4L80E handle 1000hp? ›
Our PERFORMANCE 4L80E series is ideal for street/strip driving and upgrades from a 4L60E/4L65E platform.Is a 4L80 stronger than a TH400? ›
Though 4L80E race transmissions are quite similar to TH400 in terms of strength and parts used, however, there are differences, such as the added overdrive gear, advanced electronic controls, and a lock-up torque converter. 4L80E transmissions have nearly 25% overdrive and are 4 inches longer than the TH400.How much gap between torque converter and flexplate 4L80E? ›
The converter should have 1/16” – 1/8” pull up to the flexplate for proper engagement.What is the maximum input torque for a 4L80E? ›
Maximum engine input torque for the 4L80 is 440 ft. lbs. and the maximum output torque is 885 ft. lbs.What is the stall speed of a stock 4L80E torque converter? ›
Torque converter stall speed will vary between 3000-3200 RPM and is based on rear gear, weight and size of camshaft.What is the strongest 4 speed transmission? ›
Available with nearly any ratio you can think of, the G-101 is the ultimate 4 speed.
1. Driving on the Highway. The main purpose of the overdrive function is to make your vehicle more efficient and quieter on the highway. Hence, whenever you drive at higher speeds – north of 50 mph, I recommend engaging the feature.What transmission fluid for 4L80E? ›
|Manufacturer||Transmission Type||Transmission Fluid|
|ROLLS ROYCE||4L80E||DEXRON III|
A local transmission shop will rebuild a 4L60E for around $900 to $1,200 and a 4L80E for $1,300 to $1,800, with used units going for about $400 and $600 to $1,000, respectively.Can you paddle shift a 4L80E? ›
Electronic Transmission: The paddle shifter pairs only with electronic automatic transmissions such as a 4L60E, 4L80E, AODE, 4R70W, 4R100, 6R80E, 6L80E, 8L90E, 10L80E and TCI 6X. Automatic transmissions, such as the 700-R4, TH350, TH400, PG and 2004R, are not compatible with the paddle shifter.What are the benefits of a 4L80? ›
First and foremost, the 4L80E is a very strong transmission stock, and is built around the old turbo 400 platform and features the same gear ratio, however with the added advantage of a 0.75:1 overdrive to help reduce the engine's RPMs at highway cruising speeds, and if built correctly, the 4L80E transmission has been ...What is the final gear ratio of a 4L80? ›
When Manual 3, 2 or 1 is selected, the overrun clutch drum is applied through a passage connected by the manual valve, which provides engine braking and also backs up the roller clutch, providing a stronger connection to the OD planetary driving the forward drum (Figure 2).How big is a 4L80E compared to a Turbo 400? ›
The 4L80E's case is 112 inches longer than a Turbo 400, and it has an integral bellhousing that's offered with a Chevrolet V8 bolt pattern.Is 6L80E stronger than 4L80E? ›
"Stock versus stock, the 4L80E and 6L80E are very similar in terms of strength," explains Kyle House of Circle D. "The main difference is that the 6L80E has much more versatile gear ratios.What is needed for 4L80E swap? ›
In almost every case, you will need to build (or buy) a new transmission crossmember, a new torque converter, a set of transmission lines, a modified or swap harness, and a modified driveshaft with a larger yoke and crossover U-joint.
When the torque converter starts malfunctioning, you may feel shuddering and even slipping in overdrive. You usually notice your car shuddering because it feels like it's vibrating. Your car will vibrate even when you're not going very fast. The shuddering makes the car lag and is very noticeable.What is the spline count on a 4L80E? ›
The 4L80E featured a large 32 spline output shaft (even though much stronger) in its various 2wd and 4wd applications.Should there be a gap between torque converter and flexplate? ›
You should observe 1/8” (. 125”) to 3/16” (. 187”) of air gap between the torque converter mounting pads and flexplate before sliding the converter forward to attach it to the flexplate. If you have 1/8” – 3/16” air gap then you may proceed with sliding the torque converter forward and attaching it to the flexplate.How much HP and torque can a 4L80E handle? ›
The GM 4L80E Performance Transmission Level 4 is powered with whopping 800 Horse Power. This automatic transmission gear can also generate up to 700 ft. lbs. of torque at a stall level of 2800 to 3400 rpm.How many quarts of ATF does a 4L80E hold? ›
4L80-E: 13.5 quarts.How many torque converter bolts does a 4L80E have? ›
,GM 4L80E Torque CONVERTER BOLTS (6) HEX HEAD M10-1.50 x 15mm FREE SHIPPING.What happens if torque converter stall is too low? ›
If converter stall speed is too low, the car will be lazy leaving the line; if too high, there'll be excessive high-gear slippage—either case adds time to your e.t. Engine builders use car weight and dyno data to aid selection. The converter is also matched to the transmission's gear ratios.What is the best stall speed for torque converter? ›
In general, the desired stall speed should be 500-700 RPM below the engine RPM at peak torque. This ensures a margin for application for the torque converter to take off. You don't want to have to floor your gas pedal and wait a few seconds for your vehicle to move.What is the toughest auto transmission? ›
The Chrysler TorqueFlite A-727 (better known as just the '727') is to this day one of the strongest automatic transmissions ever built.Why is the Muncie M22 called the rock crusher? ›
The reduced gear angle of the M22 created a problem with noise (hence the name "rock-crusher"). Performance seekers decided to live with the noise when the benefits of increased durability from the gear-tooth angle outweighed the gravelly clatter.
Manual transmissions require less servicing to remain functional and don't need the same type of oil as an automatic transmission. Cars with a stick-shift usually last longer than an automatic of the same make and model.When should you not use overdrive? ›
Overdrive should not be used when you need your vehicle's full power to accelerate for passing, climb a hill, tread an off-road surface, or trailer a weighted load. All of these applications require a vehicle's torque to be willfully utilized.Should you plow in overdrive? ›
Most vehicle manufacturers do not recommend snow plowing in overdrive. Consult your vehicle owners manual to find out if plowing in overdrive is recommended--and if so, when and how. Plan your plowing pattern so that you are driving forward as much as possible.Is it cheaper to rebuild or buy a transmission? ›
New transmissions can cost thousands of dollars more than rebuilt ones, and the down payment requirements for a new vehicle can be much more, depending on the vehicle you want. Rebuilt transmissions typically come with warranties, ensuring that you'll get your money's worth out of the unit.Is it cheaper to have a transmission rebuilt or replaced? ›
These factors include if it is automatic or manual, the age of the transmission and its parts, the extent of damage, and the type of vehicle. A transmission rebuild cost averages $3,000. In comparison, a transmission replacement cost averages $6,500.Is it cheaper to rebuild or get a new engine? ›
If properly done, a remanufactured engine should be as good as a new engine and it should carry a warranty for a year. And generally, it should be cheaper than a fully rebuilt engine. But you need to find out exactly who is doing the rebuilding.What is the overdrive ratio change on a 4L80E? ›
Where the original 4L80E First gear is 2.48:1, TCI created a 2.97:1 First gear ratio. Then to create a new Second gear, the overdrive is engaged 2.97 x 0.75 = 2.23:1. This creates the situation where the engine drops less rpm from First to Second gear.What is the stock gear ratio for a 4L80E? ›
The gear ratios for the 4L80E are: 1: 2.482.What is the overdrive ratio on a 4L80E? ›
The 4L80E offers several significant advantages for a wide variety of applications. The 0.75:1 overdrive ratio provides a significant reduction in cruising RPM which will help contribute to a dramatic increase in efficiency.What transmission can handle 1000 hp? ›
PERFORMANCE TH400 RACING TRANSMISSION (Auto).. supports up to 1000HP | PerformaBuilt Transmissions | Racing-Offroad-Hauling.
Mine will lock up on speeds of 55 MPH, or greater, and will unlock if I give it more than 30% throttle at ANY time.How much HP can stock 4L60E handle? ›
Their Stage 2 Pro Race transmission can handle gobs of power while their Invincible Black Edition 4L60E trans can support over 1,000 ponies.What is the strongest stock GM transmission? ›
The 10L90E is by far the biggest and heaviest modern automatic transmission in GM history, but it's also the strongest and offers amazing performance and economy when matched with a Gen V LT engine.What is the strongest truck transmission? ›
2 THE ALLISON 1000 IS THE STRONGEST DIESEL TRANSMISSION:
Just like with a Dodge transmission, once power gets past 100-150 rwhp over stock, the Allison will have problems.
ZZ572/720R Deluxe w/ 4L85E Transmission.What transmission goes with a 572 engine? ›
T56 Super Magnum six-speed manual.
Also, the 4L80E performance transmission was designed for cars up to 16,500 lbs GVWR with towing capacity up to 22,000 LBS, and whose engine is up to 440 ft. lbs. (597 N·m) of torque.How much torque can a 4L80E handle? ›
The GM 4L80E Performance Transmission Level 4 is powered with whopping 800 Horse Power. This automatic transmission gear can also generate up to 700 ft. lbs. of torque at a stall level of 2800 to 3400 rpm.Can a 4L60E handle 500hp? ›
We found a used 4L60E out of a small-block Chevy-powered 1999 van for $200 and decided on a budget upgrade to handle roughly 500 hp. This decision was shaped by the knowledge there are lots of performance upgrade parts from Sonnax and TCI Automotive.Which is better 4L60E or 4L80E? ›
The Bottom Line. The 4L60E vs 4L80E performance transmission differences are numerous. And these differences show that the 4L80E is the better transmission of the duo. However, it'll cost you more to acquire this unit compared to the 4L60E and the latter is also easier to find.