opinion on the straight 6 engine with a 4 speed

[andrew]

Hello all,

I have a '70 SIIA 88" that has been my nearly daily driver for 20 years. Rebuilt 2.25 engine with 8:1 compression and some other nice features; runs strong and well, great truck. It rarely if ever seems underpowered and--importantly--it has an overdrive that makes it possible to go on the highway. It cruises comfortably at 55-60, pretty happily at 65, and under duress at 70 mph.

I'm considering a '69 sIIA 109" with the less common stock straight 6, coupled with a 4 speed. The truck is far away from me so I cannot test drive it.

I've never driven the 6 cyl version, so I have some questions for those with more experience: How does the usability of the 6 cyl with 4 speed compare to the 4 cyl with overdrive? How does the in-town and off-road power stack up?

I love the versatility of my current 4 speed with overdrive; I don't hesitate to take it on the highway, often for long rides. I don't go fast (usually about 60 mph) but the truck is all about not being in a hurry. In the end, I don't want to "upgrade" to the 6 cyl with 4 speed and be worse off than I am.

Any thoughts and input are much appreciated. Thanks.

[RPGreg2600]

The 2.6l is much more expensive to buy parts for and seemingly less reliable, and harder to work on.

The gearing is the same as a 4 cylinder, so you'll still probably want an overdrive to keep the rpm down.

[TeriAnn]

The 2.6l is much more expensive to buy parts for and seemingly less reliable, and harder to work on.

The gearing is the same as a 4 cylinder, so you'll still probably want an overdrive to keep the rpm down.

I agree with the above. The engine runs smooth,has noticeably more power than the four cyl. engine but not by a whole lot. Cooling fan gets kind of loud above about 50 MPH. They don't seem to hold up well if you put real miles on one and as mentioned parts can be scarce & expensive. They are OK if you don't drive the truck long miles.People who do tend to replace them with a Chevy 6 & Chevy gearbox tied to a Series Transfercase with an Advance adapter in between. The six cylinder engine bay makes a swap to a Chevy six a lot easier.

A stock LR gearbox doesn't hold up as well under the extra HP of the LR six as it does under the four.