Tranny Rebuild Now: Upgrades?

[Stratosurfer]

All,
On to the next item...
Tranny is slipping on the Burb. Rebuild imminent and from what I read about on time (Right at 130K miles). I'm hoping to gain the knowledge to ask for a heav(ier) duty rebuild on the clutch-pack for towing a planned 7000lb dry RV. What are the typical mods I should ask for in a HD towing upgrade in my rebuild? My old mech (no longer in the business) said that this type of rebuild my wife may not like due to hard(er) shifting.
Any feedback appreciated. This must be done this week.

[Kick Ass Matt]

All,
On to the next item...
Tranny is slipping on the Burb. Rebuild imminent and from what I read about on time (Right at 130K miles). I'm hoping to gain the knowledge to ask for a heav(ier) duty rebuild on the clutch-pack for towing a planned 7000lb dry RV. What are the typical mods I should ask for in a HD towing upgrade in my rebuild? My old mech (no longer in the business) said that this type of rebuild my wife may not like due to hard(er) shifting.
Any feedback appreciated. This must be done this week.

Don't need a heavier rebuild. Shove the largest cooler you can fit under the grill. Hell even put in 2 coolers. Next to do is get a deep pan. Synthetic fluid is possible as well but at 15 - 17 quarts it gets expensive. I just use the regular cheap stuff and change it every year.

If you have the cash you can spring for a Gear Vendor's OD unit too...

Oh yeah also you might want to put in a deep pan for your diff...

[Robyn]

The 4L80 needs to have some good parts installed.
There are clutch upgrades as well as sprag upgrades.
The valve body needs to be checked to be sure its still fit for duty and if the bores are worn out to replace it.

All the bushings need to be replaced. A Kevlar rear band
Torque converter. (Get one with a Kevlar lockup clutch)
The transgo shift kit is a must.
Now this kit will make the shifts slightly firmer but not to the point of being obnoxious.

There are many more mods but some of these are for very high HP applications and would be more $$$ for minimal returns.

The one thing you can tell the little lady is that by doing these upgrades that the cost of doing it over wont come around again any time soon.

Be sure that the tranny cooler is flushed good and a return line filter is installed to catch any crap that has lodged inside the cooler.

Good idea on an addtional cooler BTW.

A single cooler about a foot wide by 18" long in addition to the radiator unit will do fine.

Many of the Burbs came with an extra and this should do fine.

My Son inlaw has a 99 2500 and his tranny temp never exceeds 190F when towing our 4 place horse hauler. His truck is factory stock/with tow package.


Good luck

Robyn

[Stratosurfer]

OK, perfect. I have prices of $1,500 for a local recommended shop up to $4,000 for a GM factory reconditioned. I'm thinking if I spec out the adds that Robyn has mentioned (The Burb has the towing package and has two additonal coolers in front of the radiator), that I would be much better off taking the local rebuild at $1,500 plus adds. This rather than a Jasper or GM remanufactured unit at much more, without the upgrades, just to get a national warranty.
It seems that if a tranny works at the beginning, they are usually OK, meaning more $$ for a national warranty may not pay.
Am I thinking right??...

[mafrazer1]

I damaged my 4L80e towing up a hill heading east out of Wheeling, WV on I70. With no lockup in 3rd, or in 2nd gear the temperatures quickly rose over 260 on my gage. Before I made it to the top, it started slipping and set P0756 (shift solenoid B performance or stuck off) and P1871 (not defined).
Had to stop and try to reset limp mode, which only lets you shift up to 2nd gear. Not good in the mountains, or anywhere else. When trans is in "lockup" temps are just fine, ~180 or so. Run out of lockup, and they spike off the scale.

After the codes were reset, and the trailer parked, the trans was shifting just fine in forward gears, but hesitated to engage in reverse.
My trans shop found it was slipping in 3rd under moderate acceleration.
When I receive the old parts from the rebuild I'll post pictures if there is visible evidence of wear or damage.

My repairs included a heavy duty torque converter by J&B, and a Transgo HD2 shift kit. Shifts are just fine in my view with the middle size hole for shift firmness in the valve body.

My next towing trip is some weeks in the future, I'll post a report on performance.