4L60e front pump failure
Perhaps MaroonMonster can tell us what the rotor/vane clearance is supposed to be, and how readily available narrower rotors and vanes are.
Perhaps MaroonMonster can tell us what the rotor/vane clearance is supposed to be, and how readily available narrower rotors and vanes are.
Replacements are inexpensive, plentiful, will provide healthy pump operation, TCC and Pressure-Regulator valve-train that are not worn, and fresh stator-support splines.
When we (GM) originally designed and produced these parts, the rotors and slides were selective (for the THM200-4R and THM700-R4). We produced them in 5 different sizes/ thicknesses.
The thicknesses were of the following ranges:
1. =0.7066" - 0.7071"
2. =0.7071" - 0.7076"
3. =0.7076" - 0.7081"
4. =0.7081" - 0.7086"
5. =0.7086" - 0.7091"
These were the original 7-Vane Rotors and Slides. (I do recommend using a 7-Vane Rotor if the engine used is revving 6,500+ RPM.)
Currently the pump Rotors and Slides are not really offered in different sizes... But they do vary in size... They usually measure between 0.7070" - 0.7080"
When I raise line-pressure in these units (THM200-4R and THM700-R4= approx. 290 - 300 Psi and 4L60E/ 65E/ 70E= approx. 240 - 250 Psi), I aim for 0.0020" for the Rotor and 0.0030" for the slide.
I aim for a tight 0.0015" Vane to Rotor-Slot clearance.
I would also recommend swapping out the 13-Vane Rotor in a 4L60E/ 65E/ 70E to a 10-Vane Rotor, when having a "Performance" engine in front of the transmission (Not revving past 6,200 RPM).
Lastly, I do NOT recommend that anyone spend their $$$ on a Billet-Steel pump Rotor...
A stock pump Rotor should not be breaking.
If it does break, then there is an issue with clearances or alignment... These rotors do not break from Horse-Power/ Torque.
I have stock 7-Vane Rotors living perfectly fine with engines making 1,200 HP and turning 7,500 RPM.
I do however recommend replacing the stock pump Rings for a pair of TransGo or "UnBreakable-rings".
Last edited by vorteciroc; Feb 25, 2021 at 01:45 AM.
This is GM part #24236486.
It is sold "Complete" with new TCC valve-train, PR valve-train, Boost valve-train, seals, ISS dummy-plug, pump-bolts, Etc...
It is for the 300mm style Input-Shaft with Input-Speed Sensor Reluctor-Teeth.
If you have a 300mm style Input-Shaft without the ISS Reluctor-Teeth...
You will have to get an After-Market or GM Input-Shaft with the ISS Reluctor-Teeth and install the ISS Dummy-Plug Included with GM #24236486.
GM part #24243749 is the front side of the Pump-Assembly with matching passages.
It is sold "Complete" with new Rotor, Vanes, Slide, Slide-Spring, seals, pump-bolts, Etc...
GM part #24236486 is currently $113 on Amazon
GM part #24243749 is currently $163 on Amazon

...and Thank You.
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GM part #24243749 is for later 2004 or 2005+ 4L60E/4L65E which use a metal clad seal on the case into which the pump seals.
GM part #24230110 is for earlier 4L60E which use a o-ring which fits into a grove around the pump to seal against the case.
Note that ISS (Input Speed Sensors) came out a bit later, e.g. some 2006 and many/most 2007 models.
Therefore, some 2004 or 2005 may have the metal clad seal but still be pre-ISS. (So many incompatible versions and parts for the 4L60E.)
As Vorteciroc wrote, the GM part #24236486 is for ISS models. The ISS and non-ISS input shafts are different - besides the ISS reluctor teeth, the teflon seals are also in a different position.
Last edited by mrvedit; Mar 1, 2021 at 03:44 PM.
You were not wrong in what you posted. The two part numbers that you listed are indeed intended to go together. I just wanted to point out that the cover did not have an o-ring groove to maybe help someone avoid a pump cover/case mismatch.
Last edited by mrvedit; Feb 28, 2021 at 12:12 PM. Reason: Quoted an incorrect statement of mine
Any cores that are older than this would have used the Early design "Lathe-cut/ Square-cut" seal around the pump assembly.
Last edited by mrvedit; Feb 28, 2021 at 12:16 PM.
mrvedit, I have noticed that you have for a long while you go
out of your way to help people, Just speaking for myself, there has been countless times youve indirectly kept me out of trouble or lead me in the right direction when i was having trouble. Mixing a iss pump with 04 and below imput shaft is one example. Thank you!
Replacements are inexpensive, plentiful, will provide healthy pump operation, TCC and Pressure-Regulator valve-train that are not worn, and fresh stator-support splines.
When we (GM) originally designed and produced these parts, the rotors and slides were selective (for the THM200-4R and THM700-R4). We produced them in 5 different sizes/ thicknesses.
The thicknesses were of the following ranges:
1. =0.7066" - 0.7071"
2. =0.7071" - 0.7076"
3. =0.7076" - 0.7081"
4. =0.7081" - 0.7086"
5. =0.7086" - 0.7091"
These were the original 7-Vane Rotors and Slides. (I do recommend using a 7-Vane Rotor if the engine used is revving 6,500+ RPM.)
Currently the pump Rotors and Slides are not really offered in different sizes... But they do vary in size... They usually measure between 0.7070" - 0.7080"
When I raise line-pressure in these units (THM200-4R and THM700-R4= approx. 290 - 300 Psi and 4L60E/ 65E/ 70E= approx. 240 - 250 Psi), I aim for 0.0020" for the Rotor and 0.0030" for the slide.
I aim for a tight 0.0015" Vane to Rotor-Slot clearance.
I would also recommend swapping out the 13-Vane Rotor in a 4L60E/ 65E/ 70E to a 10-Vane Rotor, when having a "Performance" engine in front of the transmission (Not revving past 6,200 RPM).
Lastly, I do NOT recommend that anyone spend their $$$ on a Billet-Steel pump Rotor...
A stock pump Rotor should not be breaking.
If it does break, then there is an issue with clearances or alignment... These rotors do not break from Horse-Power/ Torque.
I have stock 7-Vane Rotors living perfectly fine with engines making 1,200 HP and turning 7,500 RPM.
I do however recommend replacing the stock pump Rings for a pair of TransGo or "UnBreakable-rings".









