My first question:

Did ford make only one manual transmission for the eighties style F-250/350's or are there differences between the manual trannys that are mated up to the 6.9 vs the gas jobs?

Question 2:

Is yanking the 351 out of my '88 F250 and putting in the 6.9 I've got sitting in a parts truck equivalent to.. say... swapping a 305 chevy for a 350... smell what I'm stinkin?

Thanks in advance for your insight

 

The 4spds will interchange but have different gear ratios between gas and diesel.
The diesel T19 has a lot higher granny low and closer ratio between gears 4th is the same 1 to 1 in both.

So you can use it, personally what I use mine for I like gas tranny with the lower granny better. I even have one ready if my clutch ever goes out in my dually. I'm just too lazy to change it just because I like them better.

 

Ok I spaced question # 2 it is a little more the only extra will be the gp wiring but should not be that big a problem. What years are you dealing with.

 

If you put that 6.9 in there I would use the front suspension from the donor. The 6.9 is alot heavier than the 351 and you will be wanting it as well as the spindles and hubs. The stuff for the small blocks will not carry the wieght.

 

That's sort of what I was thinking. What's easier, pulling all that stuff out from underneath the diesel and installing into the gasser chassis, or just switching the bodies and tranny if need be?

 

The 6.9 is a an '88 and is actually a single wheel one ton. The gas job is a '89 3/4 ton.
My gasser has a good body and frame with a 5 speed manual, but a tired gas guzzeling 351. My 6.9 is more rotten than last nights turd, but has a solid motor and automatic tranny. So I want to put my 6.9 in my F250 and keep my manual tranny.

My biggest question, which you answered indirectly, is there any issues mating my 5 speed tranny out of my gas truck up to my 6.9. And the answer I got was it should fit just fine but the gear ratios are a little different.. right?

Thanks for the advice on the front end, I didn't even consider that.. I was already planning on putting the 1 ton rear end under my F250 if I made the engine swap. Now I'll do the front... especially since it's a plow truck.

AND... I've already got the glow plug situation handled cause I rewired them in the ol' F350 so I could run 'em manually with a button inside. (everyone told me not to.. but it works great!)

 

I had probabaly 6 hours to get to this point total but there was no rusty bolts any where.

 

The 5 speed behind your 351 is a ZF tranny and it has an integral bell housing meaning it will only work behind 300 inline 6, 302 and 351W because of the bolt pattern to bolt it to the back of the engine.

The 4 speed behind the 6.9 is a Bog Warner tranny with a removable bell housing. All you would need to do is un-bolt the bell housing from the transmission, 4 bolts hold it on and then find a bell housing that matches the other motor, for example if you wanted to put it behind your 351, you find that style bell and bolt it in place of the 6.9 bell and bolt it all up.

They do make a ZF 5 speed for the 6.9/ 7.3 diesel pickup, but you will need to find one from a 1988 or newer i beleve behind a 7.3 since Ford did not put them behind the 6.9 factory. The 6.9 and 7.3 share bell housing bolt pattern so it would be no problem to hook up the newer ZF tranny that was made for the diesel.

Personally the over drive of the ZF would be a good fit for the diesel to lower high way RPM's, but the 4 speed is a very soild, dependable tranny too, just higer revs down the road. The C6 currently behind your diesel is also bullet proof and a very good transmission, but just like the T-19 it has a 1-1 ratio in high gear so you have high rpm's at road speed.

As far as swapping front end parts, I could be wrong, but I do not think the spindels are any different for a 3/4 pickup with or with out the diesel engine. There is no doubt the solid front end of the of the F-350 is more desirable than the IFS set up on the 3/4 ton, but it should work fine.

Jeff

 

Big block is right the 5 spds will not interchange. if you have a solid axle d60 it will bolt in and is the stoughtest one by far. (we are talking 4X here aren't we)
I don't know what year the 350 went to the solid axle is yours a D 60. if not is the diesel a supercab or standard cab.
If your diesel pickup is a standard it will have a 44 the 350 should have a 50 or possibly a 60 so I would stay with it and just change the springs if anything.

 

Ok I got it wrong the 88 body you will be keeping is the 250 so will not have the d60.
The 6.9 I guess is the 350 so no D60 either are we talking standard cabs or supercabs.
Are they the same gear ratios.

 

A lot of the gassers used dana 44 front with 8 lug hubs and they were not as tough as the dana 50 8 lug (didn't need to hold the extra wieght of the that 6.9 either). Some guys have kept the d44 front and had no problems but if you have the parts there to do the swap why not use the better stuff?

 

Most diesel standard cab pickups have a D44 They hold the weight fine but are not as tough as the D50.
I see why I was confused on the year models the 88 with a 6.9 should be 7.3 unless the engine has been changed and C6. I'm not sure when they quit using the d44 so even if the 88 is a standard cab it could be a 50 and so could the 89.

 

wheew. Thats a lot to take in. My '88 350 with the 6.9 is a standard cab, and could be an '87. The '89 250 with the 351 is also a standard cab.

 

Ok 87 was the lest year for the 6.9 but was the best year as it had the 7.3 upgrades.
At some point they quit using the D44 in the standard iirc , I'm not sure what year if you are going to use for a plow truck and one of them has a d50 I would use it. It is a bolt in swap. The lockout hub will be bigger on the 50.