The Stovebolt Site Forums The Shop Area Driveline Colorado transmissions

......the chev S 10's in the local boneyards are getting pretty picked over. Does anyone have any experience with chev Colorado drive lines ? Do the Colorados use the same T5 transmission (and bolt pattern) as the S 10's ? The rear axle looks to be the same width and the 6 bolt hubs look like a direct replacement. Soooo...has anyone any experience with Colorado transmissions swapped into an AD pickup ? Thanks all...

No on the T5.
Uses NVG1500, bellhousing is part of the transmission case front half, not the common chevy pattern either.

The Colorado rear axles are indeed the same approximate width, wheel bolt pattern is the same, but the pinion is located 2 inches off center to the right, as is the engine and transmission. I installed 1 in my 40 GMC and am fighting a driveshaft vibration problem. Hopefully changing the up/down pinion angle will help.

Joe

Joe.....that's escellent information about the pinion off set ! Thanks for that. Does that sorta make these rear ends a poor choice or will correct drive line angle (up /down) solve the issue ?

Most engine/trans combinations come 3 to 5 degrees down at the rear, which should be matched by the rear axle in a LOADED situation. That means the pinion would be up the same number of degrees as the engine/trans is down. Angle gauges are readily available to address this situation.

If one has an offset pinion, both the engine/trans should be parallel to the pinion, easy to measure with proper scale.

Ed

...wellllll.... if the pinion is off set laterally, then in an AD situation the engine and trans will never be parallel and Joes vibration issue will not get fixed.

If the pinion is angled up at the same angle as the rear of the transmission, then they will be parallel (and on the same plane.) Both the engine and pinion shaft also need to be parallel to the centerline of the truck (and thus parallel to each other.) The driveshaft would need to have the same angle on both ends and should work OK as long as the total angle (considering both horizontal and vertical angles). Here's a pic stolen from DrivelinesNW. The driveshaft would look like the picture both from the top and the side.

..... not sure what all that means, especially the parallel parts. None of these diagrams relate to or deal with a lateral off set. Not that it really matters. Joes information that the pinion is off set laterally is enough to tell me that Colorado rear ends are not suitable for use in an AD truck.....or probably any vehicle with the engine on the frame center line. Thanks Joe !

Shafts don't have to be in-line with each other to be parallel. You may be confusing that. The pinion shaft and transmission tailshaft on an open driveline truck that has both on the truck centerline are parallel with each other (if extended they won't intersect). They're that way so the u-joint angles are the same on both ends of the driveshaft. The same can be said for a truck that has a pinion offset from center with the engine on center. I did say that the view from the top would look just like the view from the side in the figure I posted. As long as the u-joint angles are the same on both ends and not severely angled, it should work fine. You would just have to pay attention to the u-joint angles as well as u-joint phasing.
Joe hasn't said that was the case on his truck, just that he has vibration. There are many causes of vibration.

re-checked Joes note: " I installed 1 in my 40 GMC " Pretty sure the reference was to a Colorado rear end.

A lateral offset and a vertical offset are the same. Think of the diagram as drawing a line down the axis of rotation for the pinion and the output shaft.

The 04-2012? Colorado and Canyons use an Aisin transmission called an AR5 or MA5. They are basically the same as a Toyota R154 or Jeep AX15, but have a different input shaft and bellhousing. The shifter location is further back than the S10 T5, so it may pose clearance issues. They have a unique bellhousing too, so you will need an adapter kit to make it work for a V8 bellhousing.

I will not be working on the vibration problem until the snow goes away. Maybe 2 months. I will keep you up to date about my findings. Starts vibrating about 40and goes away at 50. Starts again at 65.

Joe

Update on the Colorado rear end vibrations I was having. With the pinion located 2'"to the right. I had set the original pinion angle at 2 degrees down. I have reset it to 0 degrees and all is fine now. what a difference 2 degrees makes.

Joe

Is that zero degrees in comparison to the engine angle?