89 GMC Cummins conversion

[v-man]

Nice truck! Gotta love those 89 Jimmy's. The dieselwrencher is right. My tranny was heating up with similar cooler placement and it was apparent my skid plate was restricting air flow so I added a fan on a toggle switch which helped. But when towing heavy my tranny temps where still on the hot side so I squeezed another cooler between the grill and the innercooler and hooked them together in a series loop. Now my tranny temps are awesome and I rarely use the fan. Keep up the nice work.