Allison 2100 vs 2500 (how to determine)

[cofrari]

Based on a sticker on my bus, I have either a 2100 or a 2500 transmission. How would you determine which transmission I have? What would you look for to differentiate a 2100 from a 2500?


In searching, there is no mention anywhere on this site of a 2100, which I thought was interesting.

[WIbluebird]

The 2000 series came in a couple different variants. I think the differences are just gearing. But overall you get the lockup torque converter and highway speed capability which is the main thing you want

[cofrari]

Originally Posted by WIbluebird

The 2000 series came in a couple different variants. I think the differences are just gearing. But overall you get the lockup torque converter and highway speed capability which is the main thing you want

So the 2100 and 2500 are just variations of the 2000?

[cadillackid]

yeah.. the 2500PTS was a wider ratio designed for school busses..



a 2400 was a variation made for long haul MD trucks..


the 2100 seems to be the standard close ratio like went in smaller variants of box trucks. and even some of the smaller IC CE200 school busses (shorties)...




but they all operate to the user the same.. in school bus configuration they are 5 speed with generally a 0.74 overdrive gear and Lockup torque converters..

[cofrari]

Originally Posted by cadillackid

the 2100 seems to be the standard close ratio like went in smaller variants of box trucks. and even some of the smaller IC CE200 school busses (shorties)...

Based on that, I assume a 2100 wouldn't be in a CE300. So I must have the 2500 if I have a CE300?

[cadillackid]

From what I’ve seen the 300s have all had the 2500PTS.. the PTS stands for pupil transport system , they are a purpose built and programmed for school busses.. these are in highway capable busses too.
Christopher

[musigenesis]

Originally Posted by cadillackid

From what I’ve seen the 300s have all had the 2500PTS.. the PTS stands for pupil transport system , they are a purpose built and programmed for school busses.. these are in highway capable busses too.
Christopher

My seller at some point told me I have an "MD2050" transmission. Did he mean 2500? I'm sure it's a 2000-series, but that's all I know.

[cadillackid]

ive never heard them labelled as MD.. but anything is possible.. there was a 2500 and a 2550.. I forget the difference...