Tech article by Jon Hanna (Admin)
Automatic Transmission Intro
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| Transmission: | |
| 700R4 Chevy 4 speed automatic with overdrive | |
| Sources: | |
| 1982-1993 Chevy 8 cyl cars and trucks. 1987 and newer models are preferred due to a redesign that corrected several problem areas. | |
| Identification: | |
| Has a one-piece cast aluminum case and bell housing design. Look for a unique slope at the bottom of the bell housing. Case length of approximately 23.5" and weighs 155-160 lbs. | |
| Adapter required? | |
| Since the 700R4 is a Chevy transmission a bell housing adapter, new flex plate and torque converter adapter must be used to bolt up to Ford engines. Likewise an adapter kit is required to mate to the Dana 20 transfer case which should include 2 adapters, a new output (main) shaft and spud shaft. | |
| Pros: | |
| The gear range is one of the best available in an automatic transmission. The low 1st gear combined with an overdrive makes it a great choice for street and trail rigs. The 700R4 is a reliable and well known with a large aftermarket following. They're fairly easy and inexpensive to come by. | |
| Cons: | |
| Well, it is a Chevy! Early versions (pre-1987) had some design problems, which gave the 700R4 a bad name, and some still prefer not to use them. However, these have been around long enough that it's not hard to find shops to build them properly. | |
| Cost: (Approximate) | |
| Transmission: $150-500 used and $800-1600 rebuilt Adapter to engine: $400 Adapter to transfer case: $500-550 | |
| Drive Shaft Mods: | |
| Total transmission is approximately 1.5" longer requiring some drive shaft modifications | |
| Bell housing: | |
| The 700R4 does not bolt up to Ford engines. An adapter kit is required. | |
| Modifications needed: | |
| The transfer case is set back further requiring a larger hole in the floor and a new and/or modified cross member. An aftermarket transmission shifter or modification to your stock automatic shifter will be required. Transfer case to floor may be tight if you don't have a body lift installed and the front drive shaft may be very close to the transmission pan depending on your lift. A smaller diameter front drive shaft or transmission pan modification may be required. |
| Manual Transmission Gear Ratios | 1st | 2nd | 3rd | 4th | 5th |
| Bronco 3 spd (6 cyl) | 3.41 | 1.86 | 1.00 | ||
| Bronco 3 spd (8 cyl) | 2.99 | 1.75 | 1.00 | ||
| NP 435 | 6.69 | 3.34 | 1.79 | 1.00 | |
| T-18 | 6.32 | 3.09 | 1.69 | 1.00 | |
| Toploader (Close ratio) | 2.32 | 1.69 | 1.29 | 1.00 | |
| Toploader (Wide ratio) | 2.78 | 1.93 | 1.35 | 1.00 | |
| Toploader (Overdrive) | 3.29 | 1.84 | 1.00 | 0.81 | |
| ZF | 5.72 | 2.94 | 1.61 | 1.00 | 0.76 |
| NV4500 (Dodge) | 5.61 | 3.04 | 1.67 | 1.00 | 0.73 |
| NV3550 | 4.01 | 2.32 | 1.40 | 1.00 | 0.78 |
