Transmission adapter questions

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Keith
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Joined: Mon Jan 07, 2013 5:48 pm
Location: Yakima, WA

Transmission adapter questions

Post by Keith »

So I am going to be doing a 6.0 swap in my 78 J20( as soon as i buy the engine). I know I will need to buy an adapter to mate this to my T18 transmission. I've been searching on google and have found some kits. What I'm wondering is if anyone has had any good experiences with any companies out there. I just want to know they are producing a good product that is worth the money they are charging. Oh, and does anyone have any advice on shipping engines. I found some on ebay and the company told me it would cost $300 to ship from them in New Hampshire to me in Wasington state. I found a better deal on craigslist for the price of the engine but have been quoted around $ 700 to ship it from east coast to me when I searched for my own shipping online. Any advice would be greatly appreciated as i have never shipped anything freight before.
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

Who makes an adapter for the Jeep V8 T-18? It's not the same as the other Jeep T-18s.

Conventional wisdom says you are stuck with the AMC V8s, unless you want to move the shifter to come up under the dash.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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jaber
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Re: Transmission adapter questions

Post by jaber »

tgreese wrote:Who makes an adapter for the Jeep V8 T-18? It's not the same as the other Jeep T-18s.
The bell will have the same bolt circle and pattern. If his is the truck T-18 it should be fine.
A lot of guys are going AOD for the extra gear, so not many keeping the T-18...
Jeff

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'51 Willys p/u
'51 Willys Parkway Conversion
'74 CJ5
'75 J-20 Wrecker
'75 J-20 Cummins service truck
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

jaber wrote:
tgreese wrote:Who makes an adapter for the Jeep V8 T-18? It's not the same as the other Jeep T-18s.
The bell will have the same bolt circle and pattern. If his is the truck T-18 it should be fine.
A lot of guys are going AOD for the extra gear, so not many keeping the T-18...

Mmm, I don't know. I looked at both Advanced and Novak, and neither claimed that their adapter would work with the long stick-out transmission.

Novak are nice folks - give them a call to be sure before you buy an engine.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

jamesdart
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Re: Transmission adapter questions

Post by jamesdart »

not what you are looking for but i just used an advance adapter amc to gm trans adapter. the plate looks simple at first but has some funky machining for the hardware, and has some funky looking hardware you cant buy out out of a catalog.

Topic author
Keith
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Joined: Mon Jan 07, 2013 5:48 pm
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Re: Transmission adapter questions

Post by Keith »

Thanks for the response. I sent emails to both advanced and novak yesterday. I'll see what they say. Honestly the main reason for looking for an adapter was to try and save money. I figured it would be cheaper ( I may be wrong). Unless I found a different trani really cheap, I can't afford to buy one, and buy an engine.

billygoat
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Re: Transmission adapter questions

Post by billygoat »

I am going to say an adapter will be a few hundred, my novak GM tranny to amc engine was about $500.
I got the tranny used with warranty for a little over $400 shipped

Now I know some adapters are less than others, but this was a hunk of precision cut plate, a machined spacer for the torgue converter, and a junk (OMIX-ADI) flexplate that I bought a different one, and some bolts.
being made to order and low volume, I understand the cost, not saying they are a rip off or anything like that, just saying I would price out a tranny that is factory for the engine.
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

Keith wrote:Thanks for the response. I sent emails to both advanced and novak yesterday. I'll see what they say. Honestly the main reason for looking for an adapter was to try and save money. I figured it would be cheaper ( I may be wrong). Unless I found a different trani really cheap, I can't afford to buy one, and buy an engine.

There's nothing wrong with the Jeep T-18, except that Jeep uses a really long input shaft and a 5" long adapter for the V8s. This puts the shifter in the same location for both the V8s and 6s (which come with the usual short shaft). It's just an idiosyncrasy of the Jeep V8s.

If you are willing to move the transmission forward, you can fit the Ford input shaft to your T-18 and use a regular Chevy bell (assuming the 6.0L is the same as all other Chevy V8s). There ar instructions for adapting the Ford T-18 to Chevys on the Novak site. http://www.novak-adapt.com/catalog/adap ... _to_gm.htm The Jeep case is a little different than the Ford, but you can drill the Chevy bell to accommodate it.

The Ford input shaft kit is available new from Parts Mike for about $200. http://www.partsmike.com/store/store.ph ... how_detail Or you can look for a junkyard T-18 and get the parts from it. It's also possible, with minor machining (drill some new holes, plug some old holes), to take the main shaft and trans-TC adapter from the Jeep transmission and combine it with a Ford T-18 to make a Ford T-18 that bolts to your transfer case.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
Keith
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Location: Yakima, WA

Re: Transmission adapter questions

Post by Keith »

Well I got the responses back today. Novak doesn't make anything that will work with the jeep t18 to a vortec 6.0. Advanced said they could put a kit together but it would cost $1200. I'm not paying that just too keep my trani. I've tried using google to see which manual transmissions will fit in my J20, but nothing help full is coming up. Does anyone know other transmissions I should look into. I just want a manual that will fit in my truck that can handle the 6.0. Once i have an idea of what to look for i'll see which ones I can find an adapter for and then search online and my local wrecking yards. Thanks for the comments and help you've given me already.

billygoat
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Re: Transmission adapter questions

Post by billygoat »

Go back to Novak and Advance and ask them, they will tell you what tranny they have kits for behind the 6.0 and which ones will bolt in direct. You will have to tell them what you are looking for - granny low, od, auto or manual, etc. Keep in mind the transfer case, you need to use one with the correct drop.
Again adapters are available for different tranny to t-case options, but way less costly if you can use one that bolts in direct
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

Why are you hung up on the Vortec 6.0L? If it's a matter of money for parts and gas, it will take decades to make back what you spend to convert it. The AMC engines are fine - dated, but at least as good as their competition in the era.

Also, this kit http://www.novak-adapt.com/catalog/adap ... t_1415.htm should work. According to Novak, all the Chevys - even Gen III - use the same bellhousing. Your J-20 V8 bellhousing is the same as used with the T-14, T-15 and '72-76 CJ-5 T-18s, and the same as used with the Cherokee and J-10 258/T-18. Jeep PN 3215152, all the same '72-79. Again, it should work, if you keep the long adapter - it's the adapter and input gear that are different.

If you are bound and determined to convert to a Chevy, give Novak a call and talk to them. Eric is the owner. Tell them what I wrote here and ask them if they have tried using this kit with the long stickout V8 T-18. If they say they have, ask them why it does not work and what can be done to make it work.

Sorry if it seems like I'm leading you by the hand here, but it seems you need a little of it. Call them, talk to them, do your homework.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
Keith
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Joined: Mon Jan 07, 2013 5:48 pm
Location: Yakima, WA

Re: Transmission adapter questions

Post by Keith »

tgreese... don't worry about leading me by the hand. I freely admit I don't know anything about transmissions. I just don't know what info to trust that i find when researching online so i ask questions here. Originally I wanted to do a diesel conversion, but couldn't find a 4bt,6bt, or 6bd1t that I could afford. I started researching online about V8 engines i could get and after some reading and comparisons I came to the Vortec 6.0. It is fuel injected which i want, had enough power for what anything I'll be doing and is pretty easy to find a good used one, and has better mpg. From talking to people i know it seemed like a better idea to get a newer engine that was built to be fuel injected rather than try and convert my 360 to it. This is my daily driver and the only rig I own so better mpg is a big deal, when i get done with school in september i will be traveling for work. I'm not expecting to get numbers like a diesel but I need to improve my numbers. With the 360 I only get 10 miles to a gallon on the highway, and I honestly don't like carburetors. I'll contact them again and ask about what you have said here. thanks

billygoat
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Re: Transmission adapter questions

Post by billygoat »

If you want better mpg, then depending on your axle ratio, you want an Over drive transmission.
If you gears are already high, then you are ok - what RPM do you run @ 60mph now?

My TBI 401 with the 4L80E hums along @ 1750rpm @ 60 mph just as happy as can be, I've seen newer V8's run closer to 1500 rpm in OD with manuals
And as much as I love these old beasts, you could swap the body onto a modern chassis and still not get the same MPG as you would with a modern truck. The 6.0 with an manual should bump you mpg's up some.
Although I will say at 10mpg you either have low axle gearing or a blown power valve, from my experience a stick should have you pushing into the teens depending on driving habits.

Topic author
Keith
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Re: Transmission adapter questions

Post by Keith »

My truck has 4:11 gears right now. I've been looking at trani's today online and started looking into the nv5400 and np435. I know these can mate up to the 6.0 and other engines.( i made sure kits were sold for this). I'm not expecting to get as good as modern trucks. I just want better than i'm getting and to get rid of my carb for fuel injection. my first car was a 66 mustang and i hated the carb in that too. How do you check for a blown power valve. Gotta go instructor is coming back. I'm using school computer for this. lol
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

There's no advantage to the NP435 over your T-18 with the short shaft kit. Functionally equivalent. And you'd have to buy a $500 conversion kit to make it work with your transfer case.

NV4500s are wildly expensive, AFAIK. And it will need to be converted.

I don't know Chevys that well, but I'd guess you could do an all-Chevrolet conversion with your 6.0L, a 700R4 or 4L80-E and a NP208 or NP241. I like the manual truck transmissions, but it seems like the automatic would be less trouble if you are dead set on the Chevy engine.

The manual transmission trucks are typically worth more than the automatics, so I'd just sell it and buy one with an automatic. Get a '74-79 with a skipping Quadratrac and kill two birds.

Your T-18 setup (including the pedals and linkage) has some parts value.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
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tgreese
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Re: Transmission adapter questions

Post by tgreese »

Another thing ...

If it's the fuel injection (carburetor hatin') that's hanging you up, I think there may have been one or two 360s that have been converted. http://fsjnetwork.com/forum/viewforum.php?f=35

Then if you slow down ont the highway and drive around town like your grandpa, that should get you into the low teens. Engine speed won't be as much of a barrier as aerodynamics, and the only effective way to deal with that is to slow down on the highway.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
Keith
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Joined: Mon Jan 07, 2013 5:48 pm
Location: Yakima, WA

Re: Transmission adapter questions

Post by Keith »

I know I'll have to buy an adapter kit one way or the other. I can't afford to buy another rig and then sell this one, or sell this one first as it's my only vehicle. I actually don't speed on the highway or in town. Hell right now the truck only gets up to 60-65 miles an hour on the highway. I looked into converting this engine to fuel injection before i started looking for a new engine. Everyone I talked to said it was better to just buy a new engine then to convert one that wasn't designed for it. I'll take another look at converting it and keep looking at engines/transmissions i can get. i'll find someone here that is better at tuning carbs than i am and see if mine is just running wrong somehow. Thank you to everyone for your responses here. I'm trying to learn as fast as i can as I'm going along.
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jeep ranch
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Re: Transmission adapter questions

Post by jeep ranch »

Keith wrote:I know I'll have to buy an adapter kit one way or the other. I can't afford to buy another rig and then sell this one, or sell this one first as it's my only vehicle. I actually don't speed on the highway or in town. Hell right now the truck only gets up to 60-65 miles an hour on the highway. I looked into converting this engine to fuel injection before i started looking for a new engine. Everyone I talked to said it was better to just buy a new engine then to convert one that wasn't designed for it. I'll take another look at converting it and keep looking at engines/transmissions i can get. i'll find someone here that is better at tuning carbs than i am and see if mine is just running wrong somehow. Thank you to everyone for your responses here. I'm trying to learn as fast as i can as I'm going along.
Ive done several chevy drive train conversions on FSJs and never regretted any of them. All Manuals, and my favorite conversion is my 78 J20. 305, NV4500 and Np205. Bullet proof drive train and parts are easy and cheap. Put a carb on it and love it. ~18 to 20 mpg. I like things simple, strong and easy to work on. It has 410 gears although would of been better with 373s. Runs down the road at 70 with no problem if I need it to. Although most of my driving is 55 to 60. NV4500s are as cheap as Ive seen them in 10 years and the GM versions seem a bit cheaper than the rest. Ive heard lots of good things about the 6.0 and would snap one up if it presented itself, although the 5.3 is a good one too. Take your time and build it the way you want.
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