4L70E Pump 1997, new other (see details) and ready to install. Fits the 4L70E. Ships fast from the USA.
A 4L60E, 4L65E or 4L70E that suddenly loses drive, or a pump that comes apart on the bench with a split rotor, is the usual reason buyers land here. This listing is the pump rotor only: a stock-style 13-vane rotor for 1997 and later pumps, made of sintered metal like the original, with a listed thickness of .7071 to .7076 inch. Industry references on the listing include 65927B, 74532C and GM 24205400 and 24205401. It is the economical repair when the pump body, slide and pocket are still good and only the rotor is damaged.
GM's pump in this family originally used a 10-vane rotor. For 1997 GM redesigned it to carry 13 vanes, a change ATSG's Wayne Colonna says was aimed at reducing pump whine and pressure regulator valve buzz. The tradeoff is less metal between the vane slots, which makes the powder-metal 13-vane rotor more likely to crack under abuse. That is why the year on this page matters: it is the rotor for a pump already set up for 13 vanes. Dropping it into an older 10-vane pump without the matching vanes and parts is not a direct swap.
The rotor is driven by the torque converter hub and carries the vanes that move fluid through the pump. The slide around it controls how much fluid the pump delivers, and the pressure regulator sets line pressure from that flow. A crack lets the rotor flex and break apart, which drops pressure across every clutch, the band and the converter clutch at once.
Confirm low pressure with a gauge, then pull the pump and inspect it. Before you order a rotor, look for the reason the last one failed. Colonna lists high line pressure from a pressure control solenoid that fails high or a sticking regulator valve, air ingestion past the filter, a restricted filter, shallow converter engagement and engine-to-transmission misalignment. Our guide to 4L70E pressure control solenoid symptoms shows how to check the solenoid by current, and the pump failure guide covers the rest of the inspection.
This rotor is listed for 1997 and later 13-vane pumps in the TH700-R4 and 4L60 family, 4L60E, 4L65E, 4L70E and 5L40E. That includes the 4L70E in Silverado, Sierra, Tahoe, Yukon and Trailblazer SS models. Count the vanes in your current pump and measure the rotor before you order, and match the reference numbers if your old rotor is legible. Send us your year and VIN if you are not sure. All of our parts for this unit are in the 4L70E collection. If your slide and rings are worn too, the complete 13-vane rotor kit with slide is the better buy, and the billet 10-vane rotor is the heavy-duty upgrade path.
If the rotor failed from pressure trouble, add a new pressure control solenoid, and for a pre-2004 unit coming apart anyway, a 1992-2003 banner rebuild kit covers the seals and frictions.
| Fits | 4L70E 1997 |
| Part type | Pump |
| Condition | New Other (See Details) |
| Brand | GM |
| Reference | TH700 |
| Ships | From the USA |
| Warranty | 1-year |
Just the rotor. It is a 13-vane sintered metal rotor. Your pump body, cover, slide, vanes and rings are separate.
Pumps before 1997 were built with 10-vane rotors. This 13-vane rotor is meant for 1997 and later pumps already set up for 13 vanes, so count the vanes in your current pump before ordering.
The listing references 65927B, 61802A, 74532C, A74532C, 42294B and GM 24205400 and 24205401. Compare these with your old rotor if the markings are readable.
There is less material between the 13 vane slots. High line pressure, air ingestion, filter restriction, poor converter engagement and misalignment add stress until the rotor breaks.
Replace the vanes, vane rings, front seal and bushing, and check the slide and pivot pin. If line pressure was high, test or replace the pressure control solenoid.
