[Skip Fix]

Jakeshoe posts here sometimes at Jake's performance has a manual valve body for the 4L80s.
http://jakesperformance.com/Transmissions.html

[jakeshoe]

A few thoughts,
A 4L80E DOES have engine braking in stock form.
You will not experience it in the OD or 4th gear position because as stated the trans must be in 1st, 2nd, or 3rd to bring on the over-run clutch pack, which gives engine braking.

The overrun clutch pack can not be engaged while the OD pack is on.

To make a 4L80E a 6 speed it requires shifting the OD clutch on to overdrive each gear. If you do this, you could only have the over-runs on in 1st, 3rd, and 5th gears of the 6 available to provide braking in only those gears.

The "4th" gear which would be 2nd over, has very little ratio change to 5th, which would be direct or 3rd on a stock unit, even when using alternate wider ratio planetaries.

So TCI likely disabled the over-runs completely when they designed their VB. VERY POOR design.

I have said since the beginning that making a 4L80E a 6 speed was a waste of time and a good trans. It takes a reliable asynchronous shifting trans and makes it a synchronous shift POS that is overusing the overdrive clutch pack and reliant on a program to make it shift properly.

I've spoken with Ken about this as I recall.

I get asked almost weekly to build a 6 speed version of a 4L80E and I will NOT do so.

[CROCIE JR]

Jakeshoe, this is and was the prob with this tranz. On the last go around with TCI and the rebuilt 6X, I thought there may have been engine breaking in some gears but was considered to random to tell for sure. They claimed to have the engine breaking issue solved. But seems physicaly impossible after reading your post. It shifted well for about 50 miles after the rebuild. Then began to act strange, and not move at all. 700lb/ft at 3600rpm WILL find the weak link.

[rtanner]

one of the mustangmags did a tci 6x on a big power build they did, trans didnt work out well at all

[rtanner]

this thread just goes to show, how some suppliers conveintly leave out important details of operation of their latest greatest whisbang doomafachi, they are selling, its pathetic, been seeing this alot last 10 years

[KEN CROCIE]

Jake: First, I'd like to thank you for the conversation and info imparted to me a while back. I found out that TCI does some internal mods ( the drilling of new passages in the case) which prevents a PCS controller from being used. The option at that point would have been to Re-case the trans with a stock case ( to be able to re-use the expensive 2.90 low gear set) and use the PCS 5spd controller. Of course that voids the lifetime warr. from TCI. It's almost fortunate the trans failed again, so that a full refund could be had.
Any recommendations from you on a trans? Kevin (Crocie jr.) and I were thinking about a 2004r from Art Carr. No disrespect to you , but I have known Art for 35 yaers. I for one have had trouble believing a 200 could hold up to big torque , but then there are the Buick GNs as proof. Any suggestion would be appreciated. Car is a 78 TA with a 535 inch alum KRE that makes 600 lbs @ 3000rpm and 690 lbs @ 4400 rpm. Has a 3.50 9"

[critter]

I'm not Jake but get a properly built 4L80e and forget the six speed. Then you'll be happy.

[jakeshoe]

Originally Posted by critter

I'm not Jake but get a properly built 4L80e and forget the six speed. Then you'll be happy.

What he said!

I'm a big fan of the 200-4R when compared to a 700 and it can be built as a strong little unit, but I would consider it a maintenance item behind a 535 cid engine.

[Ratdaddy60]

There is more to engine braking than just having the overrun clutch applied. Examples; referencing the 6X transmission, in 5th gear you have the direct and overrun clutch applied, in 4th gear you have the O.D. clutch, intermediate clutch, and the intermediate brake band applied. In 3rd gear the overrun clutch, intermediate clutch and front brake band are applied. In 2nd gear the O.D. clutch and the low/reverse band are applied. In 1st gear the overrun clutch and the low/reverse band are applied. Of course the forward clutch is applied in all these gears.
Therefore you can leave the shifter in the O.D. position and using a paddle shifter, the driver can downshift to the lower gear ranges and have engine braking.

Originally Posted by jakeshoe

A few thoughts,
A 4L80E DOES have engine braking in stock form.
You will not experience it in the OD or 4th gear position because as stated the trans must be in 1st, 2nd, or 3rd to bring on the over-run clutch pack, which gives engine braking.

The overrun clutch pack can not be engaged while the OD pack is on.

To make a 4L80E a 6 speed it requires shifting the OD clutch on to overdrive each gear. If you do this, you could only have the over-runs on in 1st, 3rd, and 5th gears of the 6 available to provide braking in only those gears.

The "4th" gear which would be 2nd over, has very little ratio change to 5th, which would be direct or 3rd on a stock unit, even when using alternate wider ratio planetaries.

So TCI likely disabled the over-runs completely when they designed their VB. VERY POOR design.

I have said since the beginning that making a 4L80E a 6 speed was a waste of time and a good trans. It takes a reliable asynchronous shifting trans and makes it a synchronous shift POS that is overusing the overdrive clutch pack and reliant on a program to make it shift properly.

I've spoken with Ken about this as I recall.

I get asked almost weekly to build a 6 speed version of a 4L80E and I will NOT do so.

[KEN CROCIE]

So Rat,you say we actually had engine braking from the paddle shifter and didn't notice ??

[Ratdaddy60]

TCI's current 6X does not have engine braking. I am only saying that is possible to modify a 4L80E valve body to provide engine braking with the shifter in the 4th gear position.
I've been told that TCI will soon offer engine braking as an option.

[Chris Petersen]

Originally Posted by Ratdaddy60

TCI's current 6X does not have engine braking. I am only saying that is possible to modify a 4L80E valve body to provide engine braking with the shifter in the 4th gear position.
I've been told that TCI will soon offer engine braking as an option.

No offence to you but...

Unless you have built one, and it works AND survives, you are just regurating the technical side of things with no proof, kind of like a ad in hot rod for TCI.

Do you build transmissions for a living?

Would you warentee a 6sp 4L80e?

The issue is, they took a 4sp auto, and are using the computer to do most of the work to make it a 6sp, rather than design a correct 6pd trans.

Think about it, the 4L80e, is basicly a TH400 with overdrive, very tough transmission, and been proven over the years. (from what, the 1960's?)

But then using the overdrive pack applied in different stages to get a 5-6sp, just does not make sence, if you have ever had one apart, really looked at it, and have a half-arse understanding how it works.

[Ratdaddy60]

No offense taken, but I've been in the automatic transmission rebuilding industry since 1974. I was an avid drag racer until 2004.

Ford turned the four speed 4R44E into a five speed 5R55E by changing the shift strategy. The six speed 4L80E accomplishes the adding of the two extra gears by the same method.

What's wrong with having the O.D clutch come on between the OEM 1st & 2nd gears and between the OEM 2nd and 3rd gears? The overrun roller clutch is plenty strong enough to handle this, especially if the transmission is using the 2001-up roller clutch.
The better way would be to have the overrun clutches to apply in the six speeds 1st, 3rd, and 5th gears.

[Overkillphil]

This 6X approach from TCI reminds me of why I never liked the whole "gear splitting" nonsense from GV. Put a high quality, properly matched torque convertor in front of a 4L80 (4 speed) and I would expect it to outperform the busy-body 6X.