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Drivetrain Mods

G

gandolphxx

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Full Member
Joined
Jan 24, 2002
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5,750
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Houston, TX
It is time to work on the drivetrain of the beast - the 2500 has the heavy duty version of the 4L80E [RPO:MN8], also known as the 4L85E - a transmission that has been around for a long time. This version has been beefed up to mate with the 8.1L V8 and is quite capable - and should be able to do better.

All of this can be done to the 4L60E that is standard on the 1500 so don't feel left out, come join the fun.

Here are some of the things to extend life, get better performance, and get off the line faster.

1. Mag-Hytec Get a deeper pan for the transmission, more fluid, better heat absorption. The 4x4's already have this.

2. Get a transmision aux cooler if you dont have one, and of course a temp gauge[cluster swap for the 1500]. GM makes one the will fit right on, Flex-a-Lite, CoolPak, B&M, etc.

3. Consider a larger rear differential cover Mag-Hytec to allow more fluid and easier maintenance. Towers take note - this is your point of failure.

And now for the fun stuff:

4. Get an upgraded torque converter, increase the stall speed from 1600 - 1800 RPM to 2600 RPM, beef it up with Kevlar clutches. This will reduce the drop in RPM that occurs with the stock TC to provide slow, smooth shifts for your great grandmother. Don't go above 2600 if you intend to tow.

Yank writeup
Another TC writeup
Precision Industries Vigalante
TCI torque converters

These are not cheap and the install price typically equals the cost of the converter. While you are doing the converter, it is a good time to re-program your transmission - this will firm up the shift intervals and improve the life - note, this will remove the sluggish shift that comes stock, more like snapping the clutch.

Transgo re-programmer <-- read this for education.
Jet Performance Power Shift

And for the real diehard there is always the Trans brake, this is probably overkill.

Well thats what I know, still learning, am sure others have better ideas and thoughts, jump in.

Next week I am having my torque converter replaced with a 2600 stall, kevlar clutches and the Transgo mod goes in at the same time - will report results when complete. ;D
 
Which way to the print page radio button....keep this little bit of info in the truck...thanks Gman.....keep it coming.... :D :D
 
02, I am going with the Transgo, found lots of good references, and my selected Tranny man likes them. Couldn't find much on the Jet Performance one, but it seems similar in function and options.

Sorry, no reccommendation, but will report results. ;D
 
Sweet! I am looking forward to hearing the results. Of course, I would really like to hear results from some "1500-tranny-mod-guinea-pig"! :cool:

Good luck - keep us posted.

helmet
 
Helmet and all you other 1500 folks, all of the above applies to your drivetrain also - I believe that the 5.3L mates with the 4L60E, not the 4L65E that is being used on the 6.0L. Not to worry, it is a good transmission - you can bump the stall speed and add a re-program kit.

The Mag-Hytec for the rear differential is equally appropriate for you towers and tough trail folks.

You don't get off that easy. ;D
 
Gandolphxx,
did you do the MAG-HYTEC diff cover mod? If you did, did you put in synthetic fluids? I watched HOT ROD TV over the weekend and they replaced the engine oil and rear diff oil with synthetic and were able to gain HP on the dyno. Anyone have thoughts on this?
 
I am looking hard at it - may not have it in time, have to do it a little later - definitely going synthetic!!! - interesting thought on gains, hadn't even considered that, looking for durability. :D
 
I just ordered the parts to beef up the rear end on My 1500 for the Whipple.., an Alburn Heavy Duty Posi unit, a set of Richmond Gears, a Heavy Duty Yoke, and Strange Engineering Axles.., I wanted to run the Mag-Hytec Cover.., but it wont clear the Track Bar on the 1500s 5 link suspension, only 1/2 inch of clearance there..... Im replacing all the the link arm bushings with Poly.. I could relocate the Track Bar to clear the cover., but dont want to get into all of that, just for the cover.. Hoping maybe they'll make one to fit.., but I doubt it, would defeat the purpose of the Extra fluid capcity....
 
butch, don't you have the locker in your truck? if so the locker is going to be better than the posi because it does not allow any movement in the diff. posi has a little give to it. oh btw, where did you get the richmond gears? thanks. Alex
 
Got the gears from My local Speed Shop..., The Alburn Posi unit is actually Stronger than the Eaton Locker., the casing is really thick on it.., I blew two Lockers on My Blazer with 36 inch tires on it., that I Off Roaded with a good bit.., put in a Heavy Duty Alburn.., and Mark Williams axles.., and Never had a problem with it after that.., and the Lockers where terrible with those tires when cornering on the street, they would Bang, and Clunk.., when taking a tight turn.... I have 4.56 gears in My Blazer to, becuase of the Large Wheels, and tires.., so that combo puts alot of stress on the Diff. The Alburn unit, and Richmond Gears Held up Great.. Igot 66K miles on those parts, and when I drop the cover, and change the Lube, evrything looks like the day it was put in., dont get Me wrong, there are some Very Heavy Duty Lockers out there.., but there Air Lockers, which are a pain, and not great on the street.., and this is My everyday driver.., although I guess I am going abit far with it.., but what the Hey.., I Love to Play..., LOL
 
UPDATE: The drivetrain is now beefed up.

1. The torque converter has been changed up to 2600 stall, closer to 2800 with the Whipple chasing it. Clutches changed to Kevlar and the back plate replaced and strengthened. Similar to a Yank 2600HD+.

2. The transgo re-program kit has been installed and broken in - wow, this baby shifts like a stick Vette now - 1st to 2nd will scare your g/f or boss. The shifts are like "right now!".

It drives smoother, quicker and faster. I am impressed and delighted, cost less than I expected and exceeds my expectations.

Cheers ;D

Need to wire up the SCU2000 [$25 on Ebay] and still looking at the Mag-Hytec, which I think will just fit.
 
Sounds great, g_xx!!

This may be a dumb question but it won't be my first! ?How does the Trans-go re-program kit compare to what the Hypertech PP3 shift firmness program does? ?I know that there is, or was, no PP3 available for the 2500, but with one available (and already purchased) for my 1500, does it accomplish the same thing? ?Sounds very similar from the write-up and results noted. ?Thoughts on this, Butch?
Thanks! ;D ;D

RPH
 
Butch can probably do better justice to this question. In my research I came across the issue of transmission wear and performance, Transgo was frequently mentioned, and I started looking at the results - I became a believer.

Basically the Transgo reduces the shift time by restructuring the actual transmission and its behavior, the HPP3 adjusts the line pressure - will help, but may lead to transmission wear.

Here is a good reference Improving the 4L60E ;D
 
Yep.., the Hypertec just boosts line pressure.., Firms up the shifts., but does nothing to make the Trans any Stronger.., and with the Torque that a Whipple can make.., thats a Big Concern.., My friend that owns the Trans Shop says that the Higher line pressure wont hurt the Trans at all... especially if the Trans is new.., may even help in the long haul.., but is a little tougher on the Drive Train, because of the Firmer shifts..., but I wouldn't worry about that RP..... You dont have a Supercharger on Yours...., Yet..., LOL.....
 
Once again thanks for all the great info, g_xx and Butch. :D
No...no Whipple yet. Trying to head that way though. My goal is to keep all this great info straight and not mess up too much along the way!!!! ;D
This board is such a great resource for someone like me who knows just enough to be dangerous! :rolleyes:

RPH
 
Interesting side note, had to drive the '86 Bronco to the shop for an evaluation today, my better half drives it most of the time - it shifts quick just like my Transgo mod, I had forgotten how it behaved - not too shabby for 16 years and 100000 miles - still going strong.

We are thinking of getting it painted and fixed up a little.
 
Well.., the Converter, Trans, and Rear End are all done... I installed Heavy Duty U-Joins on the Drive Shafts at the same time..., the Higher Stall Converter.., and Lower Gear in the Trans..., has made a Huge difference in getting this Heavy Truck moving..., I can spin the tires with no problem in First gear now.., and Chirp them pretty good on the 1-2 shift.., ill be going to the Track soon.., to base line the truck, without the Supercharger..., then taking some vacation time to put the Whipple on.., will be interesting to see what the truck can do, with the Mods Ive done without the Blower.., then with the Whipple.......
 
Give me a second...I have to wipe the drool off the keyboard... :D :D
 
Butch, What didn't you like about the air lockers?
 
Didn't like the way the Heavy Duty units Clunked when cornering steelheadchaser.., the Heavy Duty Alburn Posi.., didn't have that problem.., and performed just as well as the Lockers..., and it has a really thick case.., I cracked a case on one of the Lockers I had in My Blazer.., so I stuck with the Alburn.., because I had Good Luck with it before..., and unlike the stock locker in the truck.., it doesn't require any Wheel Spin to lock it up.., I know that thing would have Died behind the Whipple..., some of the newer Lockers out now, may not have the Clunking problems anymore.., but the Alburn unit works so well.., I went with it......
 
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