The truck is lifted 2” (cranked and aal) running 295/75/16s and 4.88 gears (I know a bit of an over kill, previously it was on 315s which ran better but those where too big and the tires would easily catch the fenders during offroad suspension cycles and get damaged as a result) this truck doesn’t get much use, it is an offroad rig, must have done 20k miles in the last 10 years.
Anyways, I did a LS swap on my truck and at the time I kept the OE 4L60e 1 piece case trans, everything works good, from cruise control to AC to shifting in 4low. Unfortunately due to a bent rear drive shaft, it thew a u-joint cap on the slip joke and very quickly cracked the transmission’s case.
Given the circumstances at the time, I could only find a 4L60e from a 2004 Tahoe, it was taken apart, then rebuilt and installed on my truck, it went in fine and after some tuning got it to shift nicely.
Unfortunately at the time I didn’t know about the bent drive shaft so I continued to use the same bent one, which caused to crack the np243 transfer case twice, the tcase got fixed and a brand new balanced rear drive shaft was fitted to the truck.
The problem I am facing now is that the tcase adapter keeps leaking where it meets the tcase, I have taken the tcase down several times, resealed, new GM gasket with a dab of rtv etc and works for some time, after 100 miles or so it starts leaking again, this is becoming very annoying.
Since fitting the LS engine, the trans brace struts/rods were removed as those would interfere with the oil sump, following the installation of the 04 trans, the bell housing doesn’t even have the bosses to attach the rods. As I understand these are structural and got me thinking could these be the root of the problem?
The engine rests on energy suspension polyurethane mounts, these have been there for 10 years, since the time when the SBC was on the truck, the mounts got inspected and seemed fine and were re-used on the current setup. The transmission is sitting on a good GM rubber mount. This setup was never a problem, but could it be an issue now?
Did something inside the transfer case get bent with the old bad drive shaft? I am considering replacing the tcase.
So what’s your take/experience on the topic? Any help would certainly be appreciated
Many Thanks
Anyways, I did a LS swap on my truck and at the time I kept the OE 4L60e 1 piece case trans, everything works good, from cruise control to AC to shifting in 4low. Unfortunately due to a bent rear drive shaft, it thew a u-joint cap on the slip joke and very quickly cracked the transmission’s case.
Given the circumstances at the time, I could only find a 4L60e from a 2004 Tahoe, it was taken apart, then rebuilt and installed on my truck, it went in fine and after some tuning got it to shift nicely.
Unfortunately at the time I didn’t know about the bent drive shaft so I continued to use the same bent one, which caused to crack the np243 transfer case twice, the tcase got fixed and a brand new balanced rear drive shaft was fitted to the truck.
The problem I am facing now is that the tcase adapter keeps leaking where it meets the tcase, I have taken the tcase down several times, resealed, new GM gasket with a dab of rtv etc and works for some time, after 100 miles or so it starts leaking again, this is becoming very annoying.
Since fitting the LS engine, the trans brace struts/rods were removed as those would interfere with the oil sump, following the installation of the 04 trans, the bell housing doesn’t even have the bosses to attach the rods. As I understand these are structural and got me thinking could these be the root of the problem?
The engine rests on energy suspension polyurethane mounts, these have been there for 10 years, since the time when the SBC was on the truck, the mounts got inspected and seemed fine and were re-used on the current setup. The transmission is sitting on a good GM rubber mount. This setup was never a problem, but could it be an issue now?
Did something inside the transfer case get bent with the old bad drive shaft? I am considering replacing the tcase.
So what’s your take/experience on the topic? Any help would certainly be appreciated
Many Thanks