How to break in a rebuilt tranny?

[johncmng]

Do I drive the car on roads that require me to shift many time or do I take it on the freeway? Or do both? Downshifting from 5th to 4th sticks a little. Other than that the transmission is OK.

Thanks
John

[dvkk]

Do whatever you want. No special treatment is required.
I recommend changing the gear oil after 1-2k miles on a fresh rebuild.

[RoninLB]

shift concisely, deliberate and firm. Easy to figure my words as you work in 3 to 4.

[nameisbauer]

Originally Posted by RoninLB

shift concisely, deliberate and firm. Easy to figure my words as you work in 3 to 4.

Just had mine done, this was my advice too.

[Jim Sims]

Paraphrasing John Walker:


“Break-in” recommendations (with credit to John Walker): "Reluctant" shifting in one or more gears after a rebuild is typical; if you “baby” the problem, it will take longer to break-in. For example if 2nd gear is stiff; get the car’s speed up to 15 mph, push in the clutch and work the shifter back and forth between 1st and 2nd or 2nd and neutral numerous times. However, do not shift too rapidly and try and “beat the synchros” by not giving them time to work; always make the momentary “915 pause” in neutral. Then increase the car’s speed to 30 mph and do the same between 3rd and 2nd: back and forth, when it resists, keep pulling firmly so it pops into gear. Sometimes break-in takes 10 minutes, sometimes a couple of days.

After coming to a stop, “visiting” 2nd gear position initially and then moving into 1st gear is often helpful.