convertor help

[farmtrucks]

putting a 4l60 behind a 6.0 -- what flex plate and convertor do i need?

[Shon]

what flexplate is behind your 6.0, you will want to know that first....does it have a spacer on the crank?

[schwoch1]

Are you using a flat or dished flexplate. If it is flat, get a dished one from a 5.3, if yours is dished, keep the one you have. Then slot the converter bolt holes to make it work with the old style 4L60E bolt pattern, it just takes a little slot inward from the original holes to make it work. Than call up Hughes Performance in Phoenix, AZ(Summit racing carries their wares) and order their LS1 crankshaft spacer, part number HP3795 for the pilot on the converter and you will be set! If you are not comfortable with slotting the holes in the flexplate, just buy a swap flexplate (HP4004X, Summit racing's picture is wrong, stock photo) from Hughes also, although it is a little pricey and really overkill for most people.
That is the easiest way I have come across to get a LS1 to bolt to an older transmission, hope this helps!! I have done a few swaps and it works great!!!

Mike

[BR3W CITY]

agree with shon, need to know what flex plate is on there now. Motor year?
99-2000 lq4's have a slightly different circumstance with 4l60's

[farmtrucks]

I'm not certain on year - I think it is 00 or 01. I have a flat flex with no spacer -- I dont have a convertor at all.
Thanks for the help.

[farmtrucks]

motor is a 2000 model - the crank flange is thicker than a 5.3 -- now what?

[usmcchevy]

Originally Posted by farmtrucks

motor is a 2000 model - the crank flange is thicker than a 5.3 -- now what?

Does it have cast iron heads? If its a early motor with the long crank the only way to my knowledge to put a 60e behind it is a custom built converter.

[schwoch1]

If......... I remember correctly..... I stress IF... someone may be able to jump in to help...
The flexplate sits in the same spot as a normal small block chevy on that particular engine.... I think. A quick measure from bellhousing on engine to flat surface on flexplate should be able to verify this. I believe that was so they could use the old style 4L80E transmission and converter behind the Gen III motor. I still believe that you are going to have to slot a few converter bolt holes in the flexplate to get a 4L60E converter to bolt on. If I remember correctly, that flexplate is setup for the 6 pad 4L80E converter and has the larger bolt circle like the old TH400's did.
THat was like a 2 or 3 year only 6.0 that always seems to throw a wrench in the old swapping knowledge.
I know for a fact that you DO NOT have to buy a custom converter, just a little slotting of the holes will be fine.

If I were doing this, I would verify how far flexplate sits off the back of the block, compare that to a standard Small block Chevy and go from there!!
I hope this helps!!


Mike

[Clyde65]

Are you building up the 4l60e? if not, it wont last long behind the 6.0.

[schwoch1]

Originally Posted by Clyde65

Are you building up the 4l60e? if not, it wont last long behind the 6.0.

Actually, I have had 4L60E's last forever behind a 6.0 with no problems. And I have had some hard drivers with them.
GM put the 4L65E behind the 6.0 all the time, same as 4L60E with 5 pinion planets instead of 4. Planets usually don't fail on them in stock or lightly modified applications. If the poster is going to heavily modify it, or supercharge it, yah then it will die a fairly quick death. If it is a stock 300 ish horse 6.0, it will be fine, trust me!!! Keep some of the torque management in the PCM and it will last forever, and if you pull all torque management, it will still last a fairly long time!

I have been abusing a 4L60E with a stock rebuild in my '71 with a 355 LT1 with a mild cam, dyno'd at 335 HP for the last 4 years and have not had ANY problems with it!!! The 4L60E is a good transmission in the right application. Put it in the wrong setup and it won't live long, just like anything else!!!


Mike

[BR3W CITY]

Art Carr WAS doing those converters for $375, but it was a basically stock converter internals.

Just pull the crank and replace it with a Callies Dragonslayer....I mean it might be a bit overkill lol...

[schwoch1]

Originally Posted by BR3W CITY

Just pull the crank and replace it with a Callies Dragonslayer....I mean it might be a bit overkill lol...

Now THAT would take care of the problem, might as well put a stroker kit in it while you are at it..... a few turbo's, nice cam........

Mike

[farmtrucks]

It is splined to the end of shaft

[farmtrucks]

It is splined to the end

[schwoch1]

Originally Posted by farmtrucks

It is splined to the end

NOW.......... we have a problem Houston......
Because you are dealing with a late, late model 4L60E, you will need a custom converter, different flexplate, or have someone install an earlier input shaft in the trans, I think....... If you were dealing with an earlier model 4L60E, you would of had no problems. I am going to dig through some stock converter books and see if I can come up with one that will fit your bill, I am thinking of one in particular but I have to check the specifics of it.
I will keep ya posted!

Mike

[farmtrucks]

My bargain isn't turning out to be a bargain

[BR3W CITY]

ooooh ooooooh now I like were this is going... railroading someone in to a 4l80e YES.

The first one is a 4x2 trans out of a 3500 truck, this is basically what I'm using. The wiring on these SHOULD both be the same (I had my harness made for a 4l80e without telling him what year), but will require an extra VSS (has a different name but its a vss type sensor) than the 4l60e wiring.

The 4l80e is a nice place to go, stock it holds these motors no problem.

[farmtrucks]

Any more suggestions?

[BR3W CITY]

just sell the 4l60e you have and grab one of those 4l80e. Even in stock form it should hold without much of an issue.
I see it this way'
4l60e (free) + trans upgrades shift kit, servo etc (250-400$), + custom converter ($900) = $12-1400
OR
Driving condition 4l80e (~$500) + extra vss plug ($15) = $515 Leaving you with 5-700 in cash left over, which you can use to get an upgraded stall converter if you want, or use a stock verter and save the extra cash.

[clinebarger]

You can swap the Input drum & Stator support shaft for "298mm" versions & run a 98 & up 4.3L converter, Redrill the flexplate......Problem solved.

[farmtrucks]

Thanks guys for all the help and education.

I got a 5.3 laying in the floor -- I'm just gonna use it in front of the 4l60

I'll get a 4l80 to go with the 6.0 for a later build

[schwoch1]

THat would be the easiest for you at the moment!
Sorry I could not get you out of this one!!!

Mike