[Jeep Gladiator build]

Hello all need some help on my build. Got a 1966 Jeep Gladiator that's all original and is getting changed. The end result is more speed on the highway and reliability. The stock 327 AMC engine has to go and will be replaced with a Chevy 350. I have a T18 trans with a Dana 20 T case in it. The rear end is a Dana 44 and going off the manual it could either have a 3.92:1 or 4.27:1 gearing. I have 33's on the truck now and if I recall was only able to get 65 mph almost running 5000 RPMs. Way to high, don't like running my engine that high for too long. I'm open to many ideas to changing this. I've read many post about this issue and got different results. Some either used a Saturn overdrive on their Dana 18, Most changed their axle gearing to help. I know I will have to change my gearing eventually but an overdrive may help a lot. How to do it, a NV4500 trans with a Dana 300 swap or should I just change to a Dana 18 and use the Saturn overdrive. If I do a D 18 then I have to change the rear axle all together. Very confused on what to do, any help would be appreciated. Thanks

 

[jeep_boy02]

Grab a junkyard LS and auto combo and you'll be in way better shape.

I'd do D300 unless you can find a 241 C or D to match your offset.

should be wrenching or wheeling but here I be

 

[Jeep Gladiator build]

I'm trying to use some of what I have. I got a 1980's chev 350 and i want to keep it a manual. They are way more fun to drive. I think i may just change the gears in the rear end for now to get better top speed.

 

[total newb]

33 and 4.27 shouldnt be anywhere near 5k to hit 65.

Either your tach is way wrong or your gear is way deeper.

You say "gladiator". As in m715?
They dont have d44 or 4.27 gears. Should be d60-d70 with 5.89s.

 

[rowdy fitzgerald]

Definitely need to change that trans out for a 5 speed whether it’s a NV4500 or NV3500 with the correct T-case whatever model it is.

I second the junk yard LS and I’m not a chevy guy. There are so many options for aftermarket parts and they’re everywhere. I think they produce more power and get better fuel mileage than the old stock 350’s anyway.

 

[Long Tine Spork]

If you're going with a chevy motor either a nv4500 or sm465 would be good choices with a with the appropriate rear axle ratio ( as I don't believe you'll be able to find an adapter for the rambler bellhousing T18). On that note you'll probably be wanting to swap the coarse spline rear Dana 44 with a newer model J-series axle (I just finished swapping in a J20 Dana 60 into my '69 Gladiator). Front axle is a bit trickier though as later models are spring under in the front and use 2.5"instead of 2"springs. I ended up swapping a '75 full time Dodge Dana 44 and welding on new perches in mine. It's the right width, but other than that I wouldn't recommend it as they're a pain compared to later Jeep/Chevy Dana 44s.