Bolt-in shifter assembly for the NV3500 5-speed in 1988-1992 Chevy and GMC full-size trucks, replaces OE 8678461 and 404625. Not for S10 or diesel.
If your 1988-1992 Chevy or GMC full-size truck has a 5-speed stick that wanders in the gate, rattles at idle, or will not drop cleanly into a gear, the shift tower on top of the transmission is often the worn part, not the gears inside. This is a complete replacement floor shifter assembly for GM part number 8678461 (also cross-referenced as 404625), the tall aluminum tower used on C/K pickups, R/V, G-series vans, Blazer, Jimmy, Suburban and Yukon trucks with the Getrag-designed five-speed that later became the NV3500.
On these trucks the lever is not connected by a cable. The tower bolts straight to the top of the transmission, and the bottom of the stick sits in a shifter socket on the main shift rail. Moving the lever side to side rotates that rail to pick a gate; moving it fore and aft slides the rail to engage a fork. Detent rollers, plungers and a bias spring inside the transmission give the gate its feel and center the lever in the 3-4 plane. Randy's GM Getrag parts catalog lists the 1988 unit as the HM290, 1989-90 as the 5LM60, 1991-92 as the NVG 5LM60, and 1993-on as the NV3500, and shows the 8678461 tower for 1988-92 C/K trucks with the tall aluminum shift pocket. This tower is the 1st and 2nd design with no internal detent, so the gate feel comes from the detents in the transmission itself.
Grinding going into gear is a different problem. That points at worn blocker rings inside the box, which this part will not fix.
Pull the boot and bezel with the engine off and the truck in neutral. Grab the lever just above the tower and rock it. Wear in the tower bushings and pivot shows up as play you can see at the base. If the tower is tight but the truck still pops out of gear or grinds, the fault is inside: worn detents, forks or synchros. In that case new synchronizer rings or a full rebuild is the real job, and our rebuild versus replacement cost guide helps you decide which way to go on a box this old. Our manual versus automatic repair cost guide lays out what an inside-the-case repair runs compared with a bolt-on part like this.
Listed for 1988-1992 Chevrolet and GMC C/K, R/V and G-series trucks plus the Blazer, Yukon and Jimmy with the five-speed manual. GM's catalog shows 8678461 as 1988-1992 and now discontinued; one transmission parts house describes the same tower as fitting 1988-1991 four-rail trucks and not the later 3rd design with a detent. Changeovers happened during production, so check before you order: look at the bottom of your original shifter, and if the ball on the end of the lever sticks out past the bottom of the housing, this assembly will not fit. It does not fit S10 or S15 trucks (they use a separate aluminum tower) or diesel-equipped trucks, and 1993-and-later NV3500 trucks use a different tower. If you are unsure, send us your year and VIN before ordering. Other manual-box parts are listed in our transmission parts directory.
If the box is coming out for a rebuild anyway, match internal parts to your exact year: Randy's catalog shows the input bearing changed after 1991, and many NV3500 kits are built for the later 3rd-design bearings. If you are still not sure whether the noise or slop is the tower or the transmission, our transmission warning signs guide covers what each symptom points to.
| Transmission | NV3500 (also listed for Getrag 290 / HM290 / 5LM60, NV1500) |
| Replaces OE | 8678461, 404625 |
| Listed vehicles | 1988-1992 Chevy/GMC C/K, R/V, G-series, Blazer, Yukon, Jimmy |
| Base | Aluminum, no detent |
| Does not fit | S10/S15, diesel trucks, shifters whose bottom ball extends past the housing |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. This tower is the 1988-1992 design. GM parts catalogs show a different shift tower for 1993-and-later C/K trucks with the NV3500. Send us your year and VIN if you are not sure which you have.
Pull the old shifter and look at the bottom. If the ball on the end of the lever sticks out past the bottom of the housing, this assembly will not fit. The correct match has an aluminum base with no internal detent.
No. S10 and S15 trucks use their own aluminum tower, and diesel-equipped full-size trucks are excluded from the listed fitment.
No. The tower bolts to the top of the transmission and comes off with the fluid in place. Check the level at the fill plug afterward and top it up with the fluid specified for your truck.
Probably not. Grinding on engagement is usually worn synchronizer rings inside the transmission. A new shifter fixes slop, rattle and gate-finding problems that come from worn tower bushings.
